Posts Tagged ‘conjunctivitis’

Type of Drug
corticosteroids, Oral (kor-tih-koe-STER-oids)
Brand Names
Betamethasone Celestone
Gerzq(t St D?Pdient: Budesonide Entocort EC
Cortisone Acetate &I
Dexamethasone EQ Mymethasone
Fludrocortisone
Hydrocortisone Cortef
Methylprednisolone 19 Medrol
Prednisolone 10
Orapred    Pediapred
Orapred ODT    Prelone
Prednisone 0 Prednisone Intensol    Sterapred
Prescribed For
A wide variety of disorders from rash to cancer, including adrenal disease, adrenal hormone replacement, bursitis, arthritis, severe skin diseases including psoriasis and other rashes, severe or disabling allergies, asthma, drug or serum sickness, attacks of multiple sclerosis, severe respiratory diseases including pneumonitis, blood disorders, gastrointestinal (GI) disease including ulcerative colitis and Crohn’s disease, and inflammation of the nerves, heart, or other organs. Dexamethasone is also used to treat mountain sickness, vomiting, bronchial disease in premature babies, excessive hairiness, and hearing loss associated with bacterial meningitis. Fludrocortisone is used to treat Addison’s disease and for symptomatic orthostatic hypotension. Prednisone is used to improve strength and function of some muscular dystrophy patients. Methylprednisolone is used to decrease mortality in some patients suffering from severe alcoholism and chronic active hepatitis.
General Information
Produced by the adrenal gland, natural corticosteroids are hormones that affect almost every body system. The major dMeyences among corticosteroid drugs are potency and variation in secondary effects, 0OZ10r preference and past experience with a Mftosferoid usually determine which drug to prescribe for a specific disease.
Cautions and Warnings
Do not use an oral corticosteroid if you are allergic or sensitive to any of its ingredients.
Corticosteroids may mask symptoms of an infection. Because these drugs compromise the immune system, new infections may occur during corticosteroid treatment; when this happens, a relatively minor infection that would respond to ordinary treatment can turn serious. Corticosteroids may impair immune response to hepatitis B, prolonging recovery. They may reactivate dormant amebiasis (a parasitic infection). Corticosteroids should not be taken if you have a fungal blood infection, because they can allow the infection to spread more easily. They should be used with caution by people with herpes eye infection, tuberculosis or in any other bacterial, fungal, or viral infections.
Long-term use of any corticosteroid may increase the risk of developing cataracts, glaucoma, or eye infections, especially viral or fungal.
When stopping a corticosteroid, dosage must be reduced gradually under a doctor’s supervision—otherwise you may experience adrenal gland failure.
If you are taking large corticosteroid doses. you should not receive any live virus vaccine because corticosteroids interfere with the body’s reaction to the vaccine.
Hydrocortisone and cortisone may lead to high blood pressure. Other corticosteroids are less likely to affect blood pressure.
Corticosteroids should be used with caution if you have severe kidney disease.
High-dose or long-term corticosteroid therapy may aggravate or worsen stomach ulcers. This may occur when total dosage reaches 1000 mg of prednisone, 150 mg of betamethasone or dexamethasone, 5000 mg of cortisone. 4000 mg of hydrocortisone, 1000 mg of prednisolone, or 800 mg of methylprednisolone.
People who have recently stopped taking a corticosteroid and are going through a period of stress may need small doses of a rapid-acting corticosteroid, such as hydrocortisone, to get them through this period. Call your doctor if you think you might be experiencing this kind of stress reaction.
Use corticosteroids with caution if you have had a recent heart attack or have, Colitis, heart failure, high blood pressure, blood-clotting tendencies, thrombophlebitis, osteoporosis, antibiotic-resistant infections, Cushing’s disease, myasthenia gravis, metastatic cancer, diabetes, underactive thyroid disease, cirrhosis of the liver, or seizure disorders.
corticosteroid psychosis (symptoms include euphoria or feeling “high,” delirium, sleeplessness, mood swings, personality changes, and severe depression) may develop in people taking dosages greater than 40 mg a day of prednisone. These symptoms may also develop with other corticosteroids taken in equivalent doses (see “Usual Dose” for relative equivalencies). Symptoms of corticosteroid psychosis usually develop within 15-30 days of beginning treatment. These symptoms may also be linked to other factors—women and those with a family history of psychosis are more at risk.
Corticosteroids can cause loss of calcium, which may result in bone fractures and aseptic necrosis of the femoral and humorai heads (a condition in which the large bones in the hip degenerate from loss of calcium).
Prednisone may aggravate emotional instability.
Corticosteroids do not cure multiple sclerosis (MS) or slow its progression, though they may speed recovery from attacks of the disease.
. Corticosteroid products often contain tartrazine dyes and sulfite preservatives. Many people are allergic to these chemicals.
Possible Side Effects
✓    Most common: headache, respiratory infections, acne, and bruising.
✓    Common: water retention (swollen ankles), back pain, heart failure, upset stomach (possibly leading to stomach or duodenal ulcer), potassium loss, dizziness, fatigue, insomnia, weight gain, increased appetite, nausea, stomach gas, abdominal pain, general pain, muscle weakness, loss of muscle mass, slowed healing of wounds, increased sweating, allergic rash, itching, convulsions, excess hair growth, and worsening of a pre-existing psychiatric condition.
✓    Less common: irregular menstruation; slowed growth in children, particularly after lengthy periods of corticosteroid treatment; adrenal or pituitary gland suppression; diabetes; drug sensitivity or allergic reactions; blood clots; moon face; feeling unwell; euphoria; mood swings; personality Changes; and severe depression.
♦    Rare: Rare side effects can appear in any part of the body. Contact your doctor if you experience any side effect not listed above.
Drug Interactions
•    Tell your doctor if you are taking any oral anticoagulant (blood-thinning) drug. If you begin taking a corticosteroid, your anticoagulant dosage may have to be adjusted.
•    Combining a corticosteroid and a diuretic such as hydrochlorothiazide may cause loss of blood potassium. Low blood potassium may increase the side effects of digitalis drugs.
•    Contraceptive drugs, estrogen, erythromycin, azithromycin, clarithromycin, and ketoconazole may increase the risk of corticosteroid side effects.
•    Barbiturates, aminoglutethimide, phenytoin and other hydantoin anticonvulsants, rifampin, ephedrine, colestipol, and cholestyramine may reduce the effectiveness of corticosteroids.
•    Corticosteroids may decrease the effects of aspirin and other salicylates, growth hormones, and isoniazid.
•    Combining a corticosteroid and a theophylline drug may require a dosage adjustment of either or both drugs.
•    Corticosteroids may interfere with laboratory tests. Tell your doctor if you are taking any of these drugs so that tests are properly analyzed.
•    Limit your intake of alcohol while on oral corticosteroids.
Food Interactions
Take corticosteroids with food or a small amount of antacid to avoid stomach upset. If stomach upset continues, notify your doctor. Grapefruit juice doubles the amount of some oral corticosteroids absorbed into the blood.
Usual Dose
Once-daily doses should be taken in the morning. Dosages vary greatly and depend upon the specific disease being treated. Dosages for infants and children should be individualized according to severity of disease and response to treatment.
Betamethasone: starting dosage-0.6-7.2 mg a day. Maintenance 1609age-0.6-7.2 mg a day.
Budesonide: 9 mg a day.
Cortisone: starting dosage-25-300 mg a day. Maintenance dosage-25-300 mg a day.
Dexamethasone: 0.75-9 mg a day. Daily dosage sometimes exceeds 9 mg. A temporary dosage increase may be necessary it you are experiencing emotional stress. In alternate-day therapy, twice the usual daily dose is taken every other day.
Hydrocortisone: 20-240 mg a day.
Methylprednisolone: starting dosage-4-48 mg or more a day. Maintenance dosage varies. A temporary dosage increase may be necessary if you are experiencing emotional stress. in alternate-day therapy, twice the usual daily dose is taken every other day.
Prednisone and Prednisoione: 5-60 mg a day. Daily dosage sometimes exceeds 60 mg. A temporary dosage increase may be necessary if you are experiencing emotional stress. In alternate-day therapy, twice the usual daily dose is taken every other day.
Equivalent doses: Using 5 mg of prednisone as the basis for comparison, equivalent doses of other corticosteroids are 0.6 mg-0.75 mg of betamethasone, 25 mg of cortisone, 0.75 mg of dexamethasone, 20 mg of hydrocortisone, 4 mg of methylprednisolone, and 5 mg of prednisolone.
Overdosage
Symptoms of overdose are anxiety, depression or stimulation, joint or muscle pain, blurred vision, stomach bleeding, increased blood sugar, high blood pressure, and water retention. The victim should be taken to a hospital emergency room immediately. ALWAYS bring the prescription bottle or container.
Special Information
Do not stop taking this medication without your doctor’s knowledge. Suddenly stopping any corticosteroid drug may have severe consequences; the dosage must be gradually reduced by your doctor.
G& your doctor if you develop unusual weight gain, black or tarry stools, swelling of the feet or legs, muscle weakness, vomiting of blood, menstrual irregularity, prolonged sore throat, fever, cold or infection, appetite loss, nausea and vomiting, diarrhea, weight loss, weakness, dizziness, or low blood sugar.
If you take several doses a day and forget a dose, take the dose you forgot as soon as possible. It it is almost time for your next dose, skip the one you forgot and double the next dose. If you take 1 dose a day and forget a dose, skip the dose you forgot and continue with your regular schedule. Do not take a double dose.
If you take a corticosteroid every other day and forget a dose, take it immediately if you remember it in the morning of your regularly scheduled day. If it is much later in the day, skip the dose you forgot and take it the following morning, then go back to your regular schedule. Do not take a double dose.
Special Populations
Pregnancy/Breast-feeding: Studies have shown that long-term corticosteroid therapy at high dosages may cause birth defects, as may chronic corticosteroid use during the first 3 months of pregnancy. When this drug is considered crucial by your doctor, its potential benefits must be carefully weighed against its risks.
Corticosteroids taken by mouth may pass into breast milk. Most nursing mothers who must take a corticosteroid should use infant formula, though low dosages of some of these drugs may be taken for short periods while breast-feeding. Consult your doctor.
Seniors: Seniors are more likely to develop high blood pressure while taking an oral corticosteroid. Older women are more susceptible to osteoporosis (a condition characterized by loss of bone mass due to depletion of minerals, especially calcium) associated with high dosages of oral corticosteriods. Lower dosages are just as effective in seniors and cause fewer side effects.

Type of Drug
Corticosteroids, Topical
(kor-tih-koe-STER-oids)
Brand NameS
CLASS 1–Super-potent topical products
Betamethasone Dipropionate gel, ointment 0.05% 91
Diprolene gel/ointment
C/obetasol Propionate 0.05% cream, foam, gel, lotion, shampoo, ointment 19
Clobex    Olux
Cormax    Olux E
Embeline    Temovate Embeline E
Difforasone Diacetate ointment 0.05% RE Olux-E Foam    Psorcon E
Fluocinonide cream 0.1 % 0 Vanos
Flurandrenolide tape 4 MCgICM2 Rfl Cordran Tape
Halobetasol Propionate cream/ ointment 0.05%
Ultravate
CLASS 2—High-potency topical products  Amcinonide ointment 0.1 % (0
Betamethasone Dipropionate cream 0.05%
Diprolene AF
Generic Ingredients: Betamethasone Dipropionate (0.064%) + Calcipotriene (0.005%) ointment
Taclonex
Desoximetasone Cream, ointment 0.25% and 0.05%; 0.05% gel DG
Topicort    Topicort LP
Generic 10gVEOUnt.- Diflorasone Diacetate cream, ointment 0.05% 91
Apexicon    Florone E
Apexicon E    Maxiflor
Florone    Psorcon
Fluocinonide cream, gel, ointment,
solution 0.05% 9
Lidex    Lidex E
Halcinonide cream, ointment, solution 0.1 % Halog
Mometasone Furoate ointment 0.1 % 91 Elocon
Triamcinolone Acetonide ointment 0.5% RE
CLASS 3—Upper mid-strength topical products  Amcinonide lotion 0.1 % 0
Betamethasone Dipropionate cream 0.05% (a
Diprolene    Teladar
Maxivate
Generic Ingredient.- Betamethasone Valerate ointment 0.1 %
Fluocinofone Acetonide [’61 Capex Shampoo
Fluticasone Propionate cream 0.05% 9 Cutivate
Triamcinolone Acetonide cream 0.5%
Delta-Tritex    Kenonel
Flutex    Triacet
Kenalog Cream    Triderm Kenalog-H
CLASS 4—Mid-strength topical products  Amcftnide cream 0.1% D3
Betamethasone Dipropionate lotion 0.05% and foam 0.12%®
Diprosone    Maxivate Lotion
Luxiq Foam
Desoximetasone cream 0.05% 19 Topicort
Fluocinolone Acetonide
Synalar Ointment 0.025%    Synalar-HP Cream 0.2%
Flurandrenolide ointment 0.05% Cordran
Fluticasone Propionate lotion 0.05% Cutivate
Hydrocortisone Valerate ointment 0.2% ED Westcort
Mometasone Furoate cream, lotion, solution 0.1
Elocon
Prednicarbate ointment 0.1 % 10 Dermatop E
Triamcinolone Acetonide 0.1 %
Aristocort A    Delta-Tritex Cream
Aristocort Cream and    Kenalog
Ointment    Triderm
CLASS 5—Lower mid-strength topical products  Betamethasone Valerate cream, lotion 0.1
Beta-Val    Dermabet
Betatrex    Valnac
Clocortolone Pivalate cream 0.1 % Cloderm
Desonide ointment 0.0511/0
Desonate    Tridesilon
UnOwen    Verdeso Foam Lokara
Fluocinolone Acetonide cream 0.025% 91 Synalar
Flurandrenolide cream, lotion M Cordran Lotion 0.05% Cordran SP 0.05% Cordran Ointment 0.25%
Fluticasone Propionate ointment 0.005% Cutivate
Hydrocortisone Butyrate Cream, ointment, solution 0.1 0
Locoid
Hydrocortisone Probutate 0.1% Pandel
Hydrocortisone Valerate cream 0.2% RE Westcort
Prednicarbate Cream 0.1 % RE Dermatop E
CLASS 6—Mild topical products
Alclometasone Dipropionate cream, ointment 0.05% 91
Aclovate
Desonide cream, lotion 0.05% DesOwen    Tridesilon Lokara
Fluocinolone Acetonide cream, shampoo, solution 0.01%
Derma-Smoothe/FS Oil    FS Shampoo
Flurosyn    Synalar
Flurandrenolide cream DG Cordran SP 0.025%
Generic Ingredient., Triamcinoione Acetonide cream 0.1 % MS10cort
Triamcinolone Acetonide cream 0.025% Flutex    Triacet
Kenalog
CLASS 7—Least potent topical products  Hydrocortisone A
1% HC    HydroSkin
Ala-Cort    HydroTex
Ala-Scalp    Hytone
Alcortin    Ivy Soothe
Analpram-HC    Maximum Strength Bactine
Anusol-HC    Maximum Strength Cortaid
Cetacort    Maximum Strength Cortaid
Cortaid Intensive Therapy    Faststick
Cortizone-5    Maximum Strength
Cortizone-10    KeriCort-1 0
Cortizone-10 Plus    Nutracort
Cortizone-10 Quickshot    Procort
Cortizone for Kids    Proctocream-HC
Delcort    Proctofoam-HC
Extra Strength CortaGel    Stie-cort
Hemril    Synacort
Hi-Cor 1.0    Tegrin HC
Hi-Cor 2.5    Texacort Hycort
Hydrocortisone Acetate cream, ointment 0.5% and 1%G
Cortef Feminine Itch    Lanacort
Corticaine    Maximum Strength Caldecort
Cortifoam    Micort-HC
Dricort    U-Cort Gynecort Female Creme
Prescribed For
Inflammation, itching, eczema, dermatitis, vitiligo (patchy loss of skin color), blistering skin diseases, lupus and other connective tissue diseases, psoriasis, and many other specialized skin problems; may also be used to Weal severe diaper rash.
General Information
Topical corticosteroids do not cure the underlying cause of skin problems, but they can relieve symptoms of rash, itching, or inflammation by interfering with the body mechanisms that produce them. You should never use a topical corticosteroid without your doctor’s knowledge because it could mask a symptom important in diagnosing your condition. Also, improper use of a topical corticosteroid could lead to unwanted and sometimes permanent side effects. In general, ointment forms of topical steroids are more potent and usually more effective than cream or lotion forms. Ointments are also less likely to cause allergic reactions because they contain fewer inactive ingredients.
Generic products in this group can vary in potency and produce different results from their brand-name counterparts, even though they contain the identical quantity of active ingredient. Topical steroids are rated from 1 (most potent) to 7 (least potent). Generally, products within a potency class are interchangeable. Ask your doctor or pharmacist which products are interchangeable. The lowest potency products are available without a prescription. Ointments tend to be more potent than creams and solutions and different product concentrations affect their classification.
Super-potent topical corticosteroids (class 1) should not be used on the face, neck, under the arms, or in the groin area. These products are generally reserved for situations in which less potent products have not worked. They should be used with caution, and should only be applied to the areas that are affected with the rash. Using a product in this category for longer than 2 weeks at a time increases the risk of permanent skin damage.
High-potency topical corticosteroids (classes 2 and 3) are best for the trunk, arms, and legs, but should not be used on the face, neck, under the arms, or in the groin area. Using a product in this category for longer than 2 weeks at a time increases the risk of permanent skin damage.
Intermediate-potency topical corticosteroids (classes 4 and 5) can be used in children for up to 1-2 weeks at a time. This type of medication is best for the trunk and extremities. It is safer for use on thin skin, and less effective on thicker skin.
Low-potency topical corticosteroids (classes 6 and 7) can be used on any part of the body, and can be used in children. They are the best choice for the face, uadera~m area, groin, neck, and i ftl Occluded areas such as skin folds.
Cautions and Warnings
Do not use a topical corticosteroid if you are allergic or sensitive to corticosteroids or to any ingredients of the aerosol, cream, gel, lotion, ointment, or solution. Do not use a topical corticosteroid as the sole treatment for bacterial skin infections such as impetigo, viral skin diseases such as herpes, fungal skin infections such as athlete’s foot, or known tuberculosis of the skin. These drugs should not be used in the ear if the eardrum is perforated. Do not use a topical corticosteroid on ulcerated skin, or to treat acne.
Skin problems can become less responsive with time if a product is applied continuously over a long period of time. This can re-
sult in a flare-up of the problem when the medication is stopped.
Using a less potent product may avoid this problem.
Rectal corticosteroid products should not be used if you have any serious bowel condition, including bowel perforation, obstruction, abscess, and systemic fungal infection.
The rectal foam is not expelled after it has been applied and may result in higher drug blood levels than those associated with rectal enema products. The risk of systemic (whole-body) side effects is greater when more of the drug enters the blood. If there is no improvement after 2 or 3 weeks of using a rectal corticosteroid, contact your doctor.
Using a topical corticosteroid around the eyes for prolonged periods may cause cataracts, glaucoma and/or permanent thinning and fragility of skin around the eyes where the corticosteroid is being applied.
Children may be more susceptible to serious systemic side effects from topical corticosteroids, including growth retardation, Cushing’s syndrome, and suppression of natural corticosteroid production, requiring a tapering of the medication, especially if the medications are applied to large areas over long periods. Super-potent topical corticosteroids are not recommended for children.
Possible Side Effects
♦ Most common: burning; itching; irritation; “steroid” acne; skin thinning, tightening, or discoloration; stretch marks; dry cracked skin; bruising; and secondary i0ection. These effects are more likely when the treated area is covered Stith al) occlusive bandage (one that prevents contact with water and air). Side effects are more likely with extended use of high-potency topical corticosteroid products and when the treated area is covered with a bandage that completely prevents skin contact with water and air.
Possible Side Effects (continued)
V Significant amounts of corticosteroids may be absorbed into the bloodstream if large amounts are used for long periods. This can result in systemic effects and may cause serious problems, particularly in people with liver disease. Systemic side effects include lightheadedness, hives, growth suppression, and adrenal suppression.
Drug Interactions None known.
Usual Dose
Adult
Cream, Ointment, Solution, Foam, and Aerosol: Apply a thin film to the skin 2-3 times a day. High- and super-potent products should be applied no more than twice a day, and should be used for short-term treatment, usually 2-3 weeks at a time. Some may have to be applied only once a day.
Rectal Enema: 100 mg nightly for 21 days.
Rectal Foam: 1 applicator’s worth, 1-2 times a day for 2-3 weeks.
Child: Dosages for children should be limited to the lowest possible potency.
Overdosage
Serious adverse effects are unlikely after accidental ingestion. Excessive use of large amounts of topical corticosteroids may cause overdose symptoms and require gradual discontinuation of the drug. Call your local poison control center or a hospital emergency room for more information. ALWAYS bring the prescription bottle or container.
Special Information
To prevent secondary infection, clean the skin before applying the drug. Apply a very thin film and rub in gently—effectiveness depends m contact area, not the thickness of the layer applied.
Do not wash, rub, or put clothing on the area until the medication has dried.
Topical corticosteroids have an additive effect: with continuous use, 1 or 2 applications a day may be as effective as 3 or more. Once the drug begins to take effect, your doctor may recommend reducing the dose to the minimum level needed to control the
condition.
Flurandrenolide tape comes with specific directions for use-, fol-
low them carefully.
If your doctor instructs you to apply plastic wrap or any other occlusive dressing, follow directions carefully. These dressings can increase the penetration of the drug into your skin by as much as 10 times, which may be a crucial element in the medication’s effectiveness. Occlusive dressings should not be used with any of the super-potent topical products.
If you are using one of these products for diaper rash, do not use tight-fitting diapers or plastic pants, which can cause too much drug to be absorbed into the blood.
Your doctor may prescribe a specific form of the product with good reason. Do not change forms without your doctor’s knowledge: a different form may not be as effective.
If you forget to administer a dose, do so as Soon as you remember. If it is almost time for your next dose, skip the one you forgot and continue with your regular schedule. Do not administer a double dose.
Special Populations
Pregnancy/Breast-feeding: Large amounts of corticosteroids applied to the skin for long periods of time may increase the risk of birth defects. When your doctor considers any of these drugs crucial, its potential benefits must be carefully weighed against its risks. Do not use any over-the-counter hydrocortisone product for more than a few days without your doctor’s knowledge.
Nursing mothers who must use a topical corticosteroid should consider using infant formula. If you apply a corticosteroid to the nipple area, be sure to completely clean the area prior to nursing. Nursing mothers should never use the highest potency corticosteroids (classes 1, 2 or 3) because of the risk of absorbing large amounts of drug into the system that could find its way into breast milk. Nursing mothers should discuss toqkoa1 corticosteroid use with their doctor befQ(e,applying any product.
Seniors: Seniors are more susceptible to high blood pressure and osteoporosis (a condition characterized by loss of bone mass due to depletion of minerals, especially calcium) associated with large dosages. These effects are unlikely with topical corticosteroids unless a high-potency medication is used over a large area for an extended period.

Brand Name
Cortisporin Otic
Generic Ingredients
Hydrocortisone + Neomycin Sulfate + Polymyxin B Sulfate RE
Other Brand Names
AK-Spore H.C. Otic    Octicair
Antibiotic    Otic-Care
Cortatrigen Ear Drops    Otocort
Drotic    Pediotic
Ear-Eze    UAD LazerSporin-C
Type of Drug
Antibiotic and corticosteroid combination.
Prescribed For
Superficial ear infection, ear inflammation or itching, and other outer ear problems.
General Information
Cortisporin Otic contains a corticosteroid to reduce inflammation and 2 antibiotics to treat local ear infections. This combination can be quite useful for local ear problems because of its dual method of action and its relatively broad applicability.
Cautions and Warnings
Do not use Cortisporin Otic if you are allergic or sensitive to any of its ingredients.
Cortisporin Otic is designed for use in the ear. It can be very damaging if placed into the eye.
Cortisporin should not be used if you have herpes simplex, vaccinia, or chickenpox. It also should not be used by patients sensitive to sulfite.
Cortisporin Otic should not be used iAyou have a perforated eardrum,
Possible Side Effects
V Local irritation, such as itching or burning, may occur as a drug sensitivity or allergic reaction.
Drug Interactions None known.
Usual Dose
3-4 drops in the affected ear 3-4 times a day. Treatment should not last beyond 10 days.
Overdosage
The amount of drug contained in each bottle is too small to cause serious problems. Call a hospital emergency room or your local poison control center for more information. If you seek treatment, ALWAYS bring the prescription bottle or container.
Special Information
Use only when prescribed by a physician. Overuse of this or similar products can result in the growth of new organisms, such as fungi. If new infections or problems appear, stop using the drug and contact your doctor.
Before administering drops, wash your hands, then hold the Closed bottle in your hand for a few minutes to warm it to body temperature. Shake well for 10 seconds. For best results, drops should not be self-administered, but given by another person. The person receiving the drops should lie on his or her side with the affected ear facing upward. Fill the dropper and instill the required number of drops directly in the ear canal.
If the drops are being given to an infant, hold the earlobe down and back to allow the drops to run in. If the drops are being given to an older child or adult, hold the earlobe up and back to allow them to run in. Do not put the dropper into the ear or allow it to touch any part of the ear or bottle. Keep the ear tilted for about 5 minutes after the drops have been put in or insert a soft cotton plug, whichever is recommended by your doctor.
If you forget to administer a dose of Cortisporin Otic, do so as soon as you remember. If it is almost time for your next dose, skip the dose you forgot and continue with your regular schedQ%e. Do not apply a double dose.
Special Populations
Pregnancy/Breast-feeding: There are no studies of Cortisporin Otic in pregnant women but it does contain a corticosteroid, which when used over long periods of time in other formulations may increase the risk of birth defects. This drug should only be used during pregnancy after carefully weighing it potential benefits against its risks. Nursing mothers who must take this drug should use in-Pant formula.
Seniors: Seniors may use this product without special restriction.

Brand Name
Cosopt
Generic Ingredients  Dorzolamide + Timolol
Type of Drug
Carbonic anhydrase inhibitor and beta blocker combination.
Prescribed For
Open-angle glaucoma and ocular hypertension.
General Information
Cosopt contains 2 glaucoma drugs that work in different ways. It is intended for people whose glaucoma does not respond to either drug used alone. Small amounts of dorzolamide and timololthe active ingredients in Cosopt–enter the bloodstream.
Cautions and Warnings
Do not use Cosopt if you are allergic or sensitive to any of its ingredients or cannot take sulfa drugs or beta blockers. Cosopt should not be used by people with bronchial asthma, severe chronic obstructive pulmonary disease, slow heart rate or heart block, heart failure, or who are in shock.
People with diabetes or an overactive thyroid should use Cosopt with caution since beta blockers can mask the signs of low blood sugar or hyperthyroidism.
Small amounts of both ingredients enter the bloodstream and can produce the same kinds of systemic (whole-body) reactions associated with larger dosages of either a sulfa drug or beta blocker. Stop using the drug at once and call your doctor if a serious reaction develops.
4lt?18b)ockers may have to be discontinued prior to major surgery because they can affect the heart’s ability to respond normally. Some people taking a beta blocker experience severe reductions in blood flow while undergoing general anesthesia.
Dorzolamide should not be used by people with kidney disease and has not been studied in people with liver disease.
People with a history of severe allergic reactions who take a beta blocker may be at increased risk of experiencing a reaction because the drug blocks part of the body’s natural allergic
response.
Timolol can worsen the muscle weakness that accompanies myasthenia gravis.
Possible Side Effects
♦    Most common: changes in sense of taste, especially bitterness or sourness; increased sensitivity to light; and a burning or stinging sensation in the eye.
♦    Common: eye redness, irritation, or itching, and blurred vision.
♦    Less common: abdominal pain, back pain, eyelid inflammation, bronchitis, cloudy vision, eye discharge or swelling, conjunctivitis (pinkeye), corneal erosion, corneal staining, lens cloudiness, cough, dizziness, dry eye, upset stomach, drug particles in the eye, eye pain, tearing, eyelid scaling, eyelid pain or discomfort, sensation of something in the eye, headache, high blood pressure, influenza, lens discoloration, nausea, sore throat, cataracts, sinus irritation, respiratory infection, urinary infection, visual problems, and retinal detachment.
•    Rare: slow heartbeat, heart block or failure, chest pain, stroke, depression, diarrhea, dry mouth, breathing difficulties, low blood pressure, stuffy nose, rash, tingling in the hands or feet, kidney stones, and vomiting. Contact your doctor if you experience any side effect not listed above.
See Dorzolamide, page 200, and Timolol, page 1129, for fur-
ther side effect information.
Drug Interactions
•    If you use more than 1 eyedrop medkc;a~mn, separate doses of these drugs tai z& Y@ast 10 minutes.
•    COSOpt can increase the effect of other carbonic anhydrase inhibitors.
•    Combining Cosopt with an oral beta blocker or another calcium antagonist may increase the risk of side effects, especially changes in heart rhythm and low blood pressure.
•    Do not combine Cosopt and another beta-blocking eyedrop.
•    Combining Cosopt and reserpine can lead to low blood pressure, slowing of heartbeat, and dizziness or fainting.
•    Combining Cosopt with digitalis and a calcium antagonist, or with quinidine, can slow heartbeat.
See Dorzolamide, page 200, and Timolol, page 1129, for further drug interactions.
Usual Dose
Adult: 1 drop in the affected eye twice a day. Child: not recommended.
Overdosage
Little is known about the effects of Cosopt overdose or accidental ingestion. Possible overdose symptoms include dizziness, headache, shortness of breath, slow heartbeat, breathing difficulties, heart attack, and nervous system effects. Call your local poison control center or a hospital emergency room for more information. If you seek treatment, ALWAYS bring the prescription bottle or container.
Special Information
Conjunctivitis (pinkeye) and eyelid reactions can occur due to an allergic reaction or as the result of local irritation. If you experience either of these problems, stop using the drug and call your doctor so that your condition can be evaluated.
To prevent infection, do not allow the eyedropper to touch your fingers, eyelids, or any surface. Wait at least 10 minutes before using any other eyedrops.
Cosopt contains benzalkonium chloride (a preservative), which may be absorbed by soft contact lenses. Remove your soft contact lenses before using the eyedrops; you may put them back in 15 minutes after a dose.
If you forget a dose of Cosopt, take it as soon as you remember. If it is almost time for your next dose, skip the forgotten dose and continue with your regular schedule.
Store Cosopt away from sunlight.
Special Populations
Pregnancy/Breast-feeding: The safety of using Cosopt is not known. When this drug is considered crucial by your doctor, its potential benefits must be carefully weighed against its risks.
It is not known if dorMlamidle passes into breast milk, though timolol does. Nursing mothers who must use Cosopt should use
infant formula.
Seniors: Seniors may use Cosopt without precaution.

Type of Drug
Carbonic-Anhydrase Inhibitors,
Eyedrops (kar-BON-ik an-HYE-drase)
Brand Names
Generic Ingredient: Dorzolamide Trusopt
Generic Ingredient: Brinzolamide Azopt
Combination Product
Generic Ingredients: Dorzolamide + Timolol Cosopt
Prescribed For  Glaucoma.
General Information
These drugs are similar to acetazolamide, a carbonic-anhydrase inhibitor taken by mouth. Carbonic anhydrase is an enzyme found in many parts of the body, including the eyes. By blocking the effects of this enzyme, dorzolamide and brinzolamide slow the production of fluid inside the eye, reducing pit:ssure. This cffc,, i3 usetul in ir83t
ino, open-angle glaucoma because the disease is characterized by elevated eye pressure. Dorzolamide and brinzolamide are sulfonamides, or sulfa drugs, and although they are administered topically, they affect the body systemically.
Cautions and Warnings
Do not use these drugs if you are allergic or sensitive to any of their ingredients or to other sulfa drugs. Small amounts of these drugs enter the bloodstream. Rarely, people using them experience side effects or allergies associated with sulfa drugs.
These drugs have not been studied in people with very poor kidney or liver function. Since these drugs are eliminated via the kidneys, people with impaired kidney function should use an alternate glaucoma medication.
These drugs have not been studied in people with acute angle-closure glaucoma.
See Timolol, page 1129, for more information on the combination product Cosopt.
Possible Side Effects
Dorzolamide
✓    Most common: eye burning, stinging, or discomfort and a bitter taste in the mouth immediately after administering the eyedrops.
✓    Less common: allergic reactions, conjunctivitis (pinkeye), blurred vision, tearing, dry eye, and increased sensitivity to bright light.
♦    Rare: headache, nausea, weakness, tiredness, rash, and kidney stones. Dorzolamide can cause the same types of side effects as other sulfa drugs, but this is very unlikely. Contact your doctor if you experience any side effects not listed above.
Brinzolamide
♦    Common: blurred vision and a bitter, sour, or unusual taste in the mouth.
♦    Less common: eyelid inflammation; conjunctivitis (pink-
eyeY, nsh; dry eye; sensation of something in the eye;
headache; eye redness, itching, discharge, or pain; and
runny nose.
✓    Rare: allergic reactions, hair loss, chest pain, diarrhea, nausea, sore throat, tearing, itchy rash, double vision, dizziness, Possible Side Effects (continued)
dry mouth, breathing difficulties, upset stomach, tired eyes, kidney pain, cornea problems, and formation of a crust or sticky sensation around the eyelid. Brinzolamide can cause the same types of side effects as other sulfa drugs, but this is very unlikely. Contact your doctor if you experience any side effect not listed above.
Drug Interactions
• If you are using more than 1 eyedrop product, separate doses of these drugs by at least 10 minutes.
Usual Dose
Adult: 1 drop in the affected eye 3 times a day. Overdosage
Accidental ingestion of a bottle of dorzolamide or brinzolamide may affect blood levels of potassium and other electrolytes. The victim should be taken to a hospital emergency room. ALWAYS bring the prescription bottle or container.
Special Information
Call your doctor and stop using your eyedrops if you develop any unusual eye reaction or condition, including swollen eyelids and conjunctivitis (pinkeye).
Vision may be temporarily blurred when using the eyedrops. Use caution when driving or operating machinery.
If you wear soft contact lenses, take them out before using the eyedrops and put them back in 15 minutes after a dose.
To prevent infection, do not allow the eyedropper tip to touch your fingers, eyelids, or any surface. Wait at least 10 minutes before using any other eyedrops.
If you forget to administer a dose, do so as soon as you remember. If it is almost time for your next dose, skip the one you forgot and continue with your regular schedule. Do not take a double dose.
Special Populations
Pregnancy/Breast-feeding: Very high dosages of dorzolamide or brinzolamide caused birth defects in animal studies. While the risks of using these drugs during pregnancy are small in people, pregnant women should use dorzolamide or brinzolamide only after discussing its potential benefits and risks with their doctors.
it is not known if these drugs pass into breast milk. Nursing mothers who must use either drug should use infant formula.
Seniors: Seniors may be more sensitive to side effects.

dextromoramide A powerful synthetic analgesic with a shorter and less sedating action than morphine. Of value in severe and intractable pain, and in terminal disease.
Dose: 5 ing or more either orally or by injection, according to need and response. Care is necessary in liver dysfunction and respiratory depression. (Palfitunt).
dextropropoxyphene An orally effective analgesic. Of value in many painful conditions, and in malignant disease its use may delay the need to resort to the opiate analgesics.
Dose: 250 ing or more daily, but doses in excess of 700 mg daily may cause toxic psychoses and convulsions. (Doloxene). See co-proxaniol.
dextrose See glucose.
diazoxide An inhibitor of insulin secretion. Dose: given orally in doses of 5 ing/kg or more daily in severe hypoglycaemia. Also of value in severe hypertensive crisis, in
doses up to 150 mg by rapid i.v. injection. Side-effects arc nausea, tachycardia and oedema. (Eudernine).
diclofenac A non-steroidal anti-inflammatory drug (NSAID) of the naproxen type, pe, and used in rheumatoid, arthritic and similar conditions.
Dose: 75-150 ing daily, after food. Suppositories of 100 nigare useful at night, but may cause local irritation. In acute conditions and in postoperative pain, doses of 75 mg once or twice a day by deep i.m. injection for not more than 2 days. (Diclomax; Voltarol). Like other NSAIDs, diclofenac may cause gastric disturbance and hypersensitivity reactions. See page 165 and Table 29.
diamorphine A derivative of morphine with a more powerful analgesic an(] cough-suppressant action. It is also less liable to cause nausea. Valuable for the relief of severe pain and the suppression of useless cough. Addiction is a constant risk owing to the euphoric effects of the drug.
Dose: 5-10 nig orally or by injection, repeated as required. For severe pain in the terminally ill, addiction is of no consequence, and much larger doses are given according to need: if necessary, by continuous infusion or a syringe-pump device.
diazepam A benzodiazepine of value in anxiety states, insomnia, acute alcoholic withdrawal, and for premedication. It also has a muscle relaxant action, and is valuable when given by injection in status epilepticus and in the control of the spasm of tetanus.
Doses: 5-30 mg daily, 10-20 mg by slow i.v. injection as required, up to a maximum of 3 mg1kg in 24 hours. Absorption after Lin. injection is unreliable. It is sometimes given as suppositories of 5-10 ing. Side-effects are drowsiness, dizziness, respiratory depression and hypersensitivity reactions. Care is IICLL’N nary in glaucoma and renal and hepatic impairment. Fxterided treatment may lead to dependence and addiction, and withdrawal should be slow to avoid the risks of precipitating toxic psychosis, confusion and convulsions. (Stesolid; Valium). See pages 177 & 136, an(] Tables 5 & 15.
dicobalt edetate A specific antidote in acute cyanide poisoning; toxic in other conditions.
Dose: 300 mg by slow i.v. injection, followed by 50 ml of glucose solution 50%, repeated if required. (Kelocyanor). Sec .odium nitrite.
dicyclomine An anticholinergic agent used to reduce gastric hyperacidity and the smooth muscle spasm of gastrointestinal disorders.
Dose: 30-60 mg daily. Side-effects
include dryness of the mouth and blurred vision. (Ivlcrbcnlyl).
didanosine An antiviral agent used in HIV infections not responding to zidovudine. Dose: 400 mg daily before food. Diarrhoea, vomiting and peripheral neuropathy are side-effects. (Videx contains didanosine with antacids). See page 144 and Table 19.
dienoes A synthetic oestrogen used as a 0.025% cream for senile or atrophic vaginitis.
diethylcarbamazine A synthetic drug used in filariasis but long-term treatment is necessary.
Dose: I mg/kg daily initially, slowly increased to 6 mg/kg daily, and continued for 21 days. Low initial doses are necessary to reduce allergic reactions due to proteins released front dead %vornis. Side-effects include headache, nausea, rash and conjunctivitis. (I letrazan). See ivermectin.

diflucortolone A corticosteroid used topically as a 0.13′0 or 0.3% cream or ointment in steroid-responsive dermatoses. Of value in resistant conditions. (Nerisone).
diflunisal An anti-inflammatory and analgesic drug (NSAID), chemically related to aspirin, but with actions and uses similar to napmxen.
Dose: 500 ilig– I g daily. Care is necessary in aspirin-sensitive patients, and in peptic ulcer. (Dolobid). See page 163 and Table 29.
Digibind A highly purified preparation of sheep-derived digoxin-specific antibodies, given by i.v. infusion in digoxin overdose or poisoning. It mobilizes digoxin from cardiac receptor sites and binds it as an inert complex which is excreted into the urine, and symptoms of digoxin toxicity subside within an hour.
Dose: depends oil the amount of digoxin absorbed; 40nigcan neutralize about 600ligofdigoxiii.
I Dim
250-500 jig initially according to need. Nausea and vomiting are often signs of overdose. If the heart rate falls below 60 beats per minute, dosage rcquiresadill.ltmclit. See page 1.11 and Table 18.
digoxin- specific antibody See Digibind.
dihydrocodeine An analgesic derived from codeine, but with a more powerful action. Of value in many painful conditions where mild analgesics are inadequate. Dose: 30 mg orally after food, or 50 ing
by i.m. or deep s.c. injection at intervals of 4-6 hours according to need. Dizziness and constipation are side-effects. MIA 18).
dihydrotachysterol A sterol related to calciterol, but with more rapid calcium-mobilizing properties. It is used mainly in hypocalcaemia and parathyroid tetany, but is sometimes effective in calciferolresistant rickets.
Dose: 200 jig daily, adjusted to need according to plasma calcium levels as a solution in oil. (AT 10).
39
digitalis The dried leaf of the foxglove. It has a powerful strengthening and regulatory action oil the heart, but is now used as digoxin.
digitoxin The most powerful cardiac glycoside of digitalis and of value in heart failure and atrial fibrillation. Absorption is rapid but excretion, which depends on metabolism by the liver, is very slow, and cumulative effects may occur.
Dose: (maintanence) requires careful .iditminent, varying from 50-200 f.ig daily.
digoxin The principal cardiac glycoside obtained from digitalis leaf. It is rapidly absorbed orally, and is widely used in cardiac failure, paroxysmal tachycardia and atrial fibrillation. The diuresis of digoxin therapy is a secondary effect following on the improvement in the renal circulation.
Dose: for rapid digitalization, 1-1.5 mg initially over 24 hours: subsequent maintenance close 62.5-500 pg daily. For slow digitalization, 250-500 pg may be given daily for about a week, with subsequent closes based on the response. Elderly patients and children respond adequately to smaller doses, and tablets of 62.5 pg (Lanoxin-111G) are available for such patients. In emergency, digoxin call be given by slow i.v. injection in closes of
diloxanide A well-tolerated aniciellicide used in chronic intestinal anicielliasis when only cysts are present in the faeces. It is also used in acute infections, 5 days after a course of metronidazole.
Dose: 1.5 g daily for 10 days. (Furamide).
diltiazem A calcium channel blocking agent, used in the prophylaxis and treatment of angina, and useful when beta-blocking agents are unsuitable or ineffective.
Dose: 180-360 nig daily, reduced in renal impairment. It may cause bradycardia, ankle oedema and hypotension. potension. (Adizen; Tildiern). Sonic long-acting products with various brand mantes are used in hypertension. They should not be regarded as interchangeable, as the duration of action may vary. See page 114 and Table 4.
dimenhydrinate An antihistamine used mainly as all antiemetic in nausea, travel sickness and vertigo.
Dose: 100-300 ing daily. It may cause more drowsiness than sonic related drugs. (Dramamine).
dimercaprol (SAL) A specific drug for the treatment of poisoning by arsenic, mercury, gold and other heavy metals.

Allergens and irritants at work
Some workplaces have very high concentrations of allergens in the air, especially if proper safety procedures are not being followed. Occupational allergies can begin with symptoms in the nose, such as sneezing, blockage or constant streaming (allergic rhinitis). You may also suffer with itchy or watery eyes (conjunctivitis), a cough, sweating and a feverish feeling. Alternatively, direct contact with the allergen can produce a skin rash (dermatitis) or itchiness and swelling (contact urticaria/nettle rash and angioedema).
If you work somewhere with an allergy risk (see pp. 133-4), be vigilant for such symptoms and see your doctor immediately. These symptoms can be the forerunners of occupational asthma, which is a serious and potentially irreversible problem. Some allergens, such as latex, can even produce anaphylactic shock (a life-threatening allergic collapse).
Skin-prick tests (see p. 91) can show if you have an allergy to a substance encountered at work.
Acting promptly gives you the best possible chance of recovery and is vital if you have occupational asthma. Only if exposure to the allergen stops promptly do you have a good chance of shaking off the asthma. See your doctor as soon as possible and ask for a referral to a chest specialist, so that a definite diagnosis can be made. This is essential if you are going to make a claim for compensation.
Far too many people with occupational asthma are just sent off with an inhaler when they first see their doctor. By delaying the moment when work is identified as the source of the problem, and the exposure to the allergen is stopped, drug treatment can turn occupational asthma into a disabling lifelong problem. Although drugs can be helpful in speeding your recovery once exposure to the allergen
Latex allergy
Sensitisation to latex usually occurs at work (see pp. 133-4), or as a result of having many surgical operations. But latex allergy sometimes occurs in allergy-prone people even though they don’t work in a high-risk job and haven’t had many operations. Some doctors think that if a child with severe allergies needs surgery, this should be done in latex-free conditions, even though the child has no allergy to latex, because of the risk that the operation will sensitise.
Latex can cause either contact dermatitis (see p. 55) or a Type I allergy, whose symptoms can include urticaria, asthma and anaphylaxis. Latex allergy often goes undiagnosed. Once sensitised, you may react to balloons, elastic bands, condoms and household gloves. Latex in the air,
due to powdered latex gloves being used, can be a hazard for someone who is highly sensitive, as can latex traces in food (see box on p. 175). Medical treatment may be problematic (see p. 98 and box on p. 249). Cross-reactions to certain foods can occur (see p. 15 and p. 51).
For those avoiding latex, there are non-latex gloves (see p. 57), and non-latex condoms. Immunotherapy (see pp. 164-9) may be useful in severe cases: it can reduce sensitivity and eliminate cross-reactions to foods.
Other hazards
This article (pp. 132-5) deals mainly with allergens at work, that is, substances which provoke classical allergies (Type I reactions). In addition, there are skin irritants and antigens in workplaces which can provoke contact dermatitis (see p. 56) or contact urticaria (see p.50).
Some of the most dangerous workplace substances are those that bring on asthma but are not allergens. These are usually called low-molecular-weight asthmagens. The most notorious of these are platinum salts, isocyanates (used in cement, in the manufacture of foam, plastics and varnishes, and for spray-painting cars, aeroplanes and boats), colophony (used as a solder in electronics), glutaraldehyde (used in hospitals for sterilisation procedures), and persulphate (used in hairdressing). Powerful respiratory equipment, supplying air from outside the area (see p. 135) is needed if you work with some of these substances, e.g. isocyanates for spray-painting cars.
has ended, they should not be seen as a way of allowing you to go on working with the offending allergen or asthmagen.
If it seems plausible that your allergies or your asthma are related to your work, your doctor should be able to give you a sickness certificate, so that you can have some time away from the workplace, to see if you recover. The medical service at your workplace may be better at diagnosing occupational asthma than your own doctor, but be cautious. In some workplaces they do operate as they should and offer genuinely confidential treatment. But there have also been cases of information being passed to the management, and workers with the early signs of occupational allergies and/or asthma being dismissed on a pretext, or made redundant, to avoid a possible compensation claim. Most occupational health services claim to be independent, but they actually have to earn the trust of the workforce. Before you make any move, ask your colleagues for their views, especially those who have worked there for many years.
Choosing a job
If you have any tendency to allergies, or come from an allergy-prone family, you should be very choosy about where you work. Try to avoid workplaces where there is heavy exposure to allergens, especially airborne allergens which can provoke asthma:
• Bakeries and flour mills, where the allergens concerned may be wheat proteins in the flour, or enzymes added to the flour mix. These allergies can take years to begin.
• Other food-processing works, particularly those dealing with tea, soyabeans, other beans (e.g. gram flour), shellfish and fish (especially if automated gutting machines are used without adequate ventilation). Food preparation and sandwich-making can cause contact urticaria, if there is prolonged contact with a particular foodstuff (e.g. tomatoes).
• Farms, docks and cotton mills – or any other workplace generating dust from plant products. On farms, it is the dust from grain and hay that is often responsible, although mould spores (see p. 121) can also be the culprit. Allergies to mites (found in hay, grain and flour) sometimes occur and eczema is the most common symptom – often called simply ‘grain itch’.
• Saw mills and joineries, because of the wood dust, especially that from hardwoods and from red cedar (Thuja plicata).
• Paper recycling plants, if there is a lot of paper dust in the air.
• Detergent and pharmaceutical factories handling enzymes – these are added to ‘biological’ washing powders and are potential allergens. The risks are less these days, as the enzymes are in granule form rather than powder.
• Factories processing natural products such as psyllium or ispaghula, which are used as laxatives. Anyone who has been sensitised should avoid taking medicines containing the offending substance in the future, because these can sometimes provoke a dangerous anaphylactic reaction.
• Hospitals, clinics and dental surgeries, mainly due to latex rubber, used in gloves and equipment. Although nursing staff and surgeons are most susceptible, other staff including hospital administrative workers can occasionally be affected. Fears about the spread of the HIV virus has led to a huge increase in the use of latex gloves in medicine and dentistry, and a consequent epidemic of latex allergy. The main problem is with powdered latex gloves, which release 15,000 times as much allergen into the air as unpowdered gloves. Unpowdered, low-allergen gloves greatly reduce the risk of latex allergy developing, and non-latex gloves are even better. There are moves to ban the import of powdered latex gloves into Britain. They are already being phased out in hospitals and other medical facilities, but progress is slow in some areas.
• Other workplaces where powdered latex gloves are used, including
Making the workplace safe for everyone
Note that these choices about employment are for the individual employees to make for their own protection - an employer cannot refuse to take anyone on because they have allergies or come from an atopic (allergy-prone) family.
The reasoning behind this is that the workplace should be safe for everyone, as far as possible. As many as one in three of the population may be susceptible to allergies, and it is clearly wrong to bar all such people from major industries. Current thinking, in most countries, is that the focus should be on getting allergens and asthmagens out of the air, not keeping the more vulnerable workers out of the workplace.
hairdressers, dental surgeries, pathology laboratories and police stations. Construction workers wearing rubber gloves are also at risk. Someone who has been sensitised by powdered latex gloves may then react to other items (see box on p.132). Those severely affected can have great problems in daily life and with medical treatment, so anyone with a strong tendency to allergy should strenuously avoid becoming sensitised.
• Factories making or using rubber items may also expose workers to the risk of latex allergy. Anything made by the ‘dipping method’ (e.g. balloons, condoms, elastic bands and gloves) is highly allergenic. Moulded rubber items, such as tyres, are much less of a problem. Neoprene and other synthetic rubber items are not allergenic.
• Chiropody and podiatry clinics, where there is a risk of allergic reactions to the fungus that causes athlete’s foot. It is inhaled on skin flakes from the patients’ feet.
• Laboratories and other workplaces where animals are kept. In the case of mice, rats and other rodents, the allergen is found in the animals’ urine, and becomes airborne as the urine dries. Insects and spiders (e.g, those reared for biological pest control), are also allergenic due to small airborne particles from their bodies. Those working closely with bees (either honeybees or bumblebees, now reared for pollinating glasshouse crops) are liable to be stung frequently, and this can lead to sting allergy (see pp. 60-61).
• Hairdressing salons, where many different items are used that are potentially allergenic, including latex gloves (see above), permanent-wave solutions and henna. The risks of contact dermatitis are also high (see p. 55).
• Greenhouses, where the enclosed conditions can lead to high levels of allergens from plants, moulds and insect pests. There may also be exposure to pesticide sprays or their residues, which can greatly aggravate any underlying tendency to allergies.
If you have ever suffered from atopic eczema, work situations that can bring on contact dermatitis should also be avoided (see p. 55).
Taking a risky job
If circumstances force you to take a job with an allergy risk, observe all the safety procedures that are in place, and where you have the option of turning on extractor fans, wearing protective gear, or simply opening doors and windows, always do so. If the safety procedures seem inadequate, talk to your trade union Safety Representative, or the local Health and Safety Executive which can run a check on safety procedures in your workplace. This will be presented to the employer as a routine check, so they need never know that a member of the workforce has contacted the HSE.
Whatever you do, if you are in a risky job, don’t smoke. At a salmon processing plant in Scotland, 40% of the smokers developed allergies (resulting in asthma) to the fish allergens in the spray from the fish-gutting machine. Non-smokers - who formed the overwhelming majority of the workers - were not affected at all. In United States cotton mills, smokers are affected by levels of cotton dust in the air that are legally defined as ’safe’, while nonsmokers remain unaffected.
Passive smoking at work is also an important issue. A recent US study showed that non-smokers were more likely to develop asthma if they worked alongside a smoker. Your employer has a duty to provide you with clean air. This includes ensuring that other employees do not impose their cigarette smoke on you.
Respiratory equipment
Where respiratory equipment is needed, your employer must provide this, and it must be the right equipment for the job. It should be inspected, tested, cleaned and repaired after each use, and filters should be replaced regularly. All this is your employer’s responsibility, but check that it is being done, and always look the mask over before you put it on.
Two different types of respiratory equipment are currently in use:
• Those that give you a supply of air from outside the work area, either from a compressed-air cylinder, or via an air-hose (airline) supplied with fresh air. In Britain these are called breathing apparatus.
• Those that use the surrounding air but filter it to remove allergens and asthmagens. In Britain these are called respirators. (In some countries this term describes any kind of respiratory equipment.) Ordinary respirators may pose problems for some asthmatics because they cannot breathe in strongly enough to draw sufficient air through the filter. Powered respirators can be the answer: they have a battery-powered unit to help with pulling in the air.
There are government regulations concerning the type of equipment required for each type of allergen and asthmagen. Large companies generally follow these regulations, but small businesses, such as local sawmills, joineries and car-repainting workshops, may not even know about them.
Any respiratory equipment that has a face mask must form a tight seal with your face. Facial hair will prevent this, and so will stubble, so shave carefully. Faces vary enormously in shape, and if your face mask does not fit, ask for a different type of mask or a different type of respiratory equipment. Persist until you get one that’s right for you.
Carry out a ‘fit check’ each and every time you wear the mask. For example, with respirators, you can check the fit by covering the air intake completely with your hand and breathing in sharply: if the mask fits properly, it should collapse onto your face, and remain stuck to your face for several seconds. Look at the manufacturer’s instruction booklet as there may be a specific fit check recommended for the equipment you are using.
If there is any difficulty in breathing through the respiratory equipment, the replaceable filter cartridge or the equipment itself should be replaced. You should also take action immediately if you can smell the substance being handled – but never rely on this as a danger sign, because an extremely small amount, way beyond the detection capacity of the human nose, may be very damaging indeed to your health.
Keep your mask on throughout the work period. If you find this impossible, talk to your employer or
line manager about getting a different kind of respiratory equipment – a powered device, for example, that assists the inflow of air.
No form of respiratory equipment provides complete protection against allergens and asthmagens: there is always the chance of some small amount getting through. This is why respiratory equipment should not be used by those who have already developed occupational asthma but want to stay in their job.
Those who really cannot change jobs (e.g, farmers) are sometimes able to use a powered respirator helmet, which allows them to go on working despite the allergen. But this is not an ideal solution from a purely health point of view. Farmers can also improve matters, where moulds are the source of allergens, by keeping all harvested crops dry and thoroughly ventilated.
A lasting problem
As long as you catch the problem early, and are no longer anywhere near the allergen, your symptoms should disappear completely, but remember that you may still be highly sensitive to the allergen, even years afterwards. For a year or two at least, avoid contact with it again, even in tiny amounts. If someone else in your family works at the same place, they may bring home traces of the allergen on their clothes and hair: ask them to leave their workclothes outside the house and shower on arriving home.
With occupational allergies to airborne food particles, it is possible that the affected individual will later react to the same food when eaten. Experiment very cautiously, especially if the allergen is fish or shellfish.
The allergy may persist long after the job has ended. In one case, doctors found that a woman who had developed ‘baker’s asthma’, while working briefly in a bakery when young, was still allergic to the enzyme additive in bread 20 years later. She suffered an asthma attack whenever she ate bread.

Various anti-allergy drugs
An allergic reaction is a lengthy, complex process, and the various anti-allergy drugs all work on different stages of that process. That is why it often makes sense to use several different drugs for the same allergic condition: they each tackle the problem in their own way.
Steroids (see p. 140) intervene at a very late stage, quelling the inflammation that follows on from an allergic reaction. Using a steroid is rather like calling the fire brigade to put out a fire, whereas using an antihistamine (see p. 138) is like having fire-proof doors, to prevent the fire spreading at an early stage. Cromoglycate-type drugs (see below) intervene at an even earlier stage. They are like basic fire prevention - teaching children not to play with matches, or fitting smoke detectors.
Anti - leukotnene drugs (see p. 149) work at roughly the same stage of the process as anti-histamines but tackle an entirely different aspect of the allergic reaction.
Cromoglycate-type drugs
These drugs are also referred to as mast-cell stabilisers or mast-cell Mockers.
There are three drugs in this group, sodium cromoglycate (also spelled cromoglicate), nedocromil sodium, and lodoxamide. All operate at an early stage of the allergic reaction, stopping it before it actually starts. They stabilise the outer membrane of the mast cells (see box on p. 12), which prevents the allergic response from occurring.
Some common brand names
Common brand names of cromoglycate-type drugs include:
inhalers - Cromogen Easi-Breathe, Intal, Tilade
eye drops - Hay-Crom, Opticrom, Rapitil, Vividrin, Viz-on nose sprays - Rynacrom, Vividrin
capsules - Nalcrom
This is a far more satisfactory way of dealing with an allergic reaction than trying to tackle it after the reaction has occurred. But from a purely practical point of view, it has a drawback. I order to work at all, these drugs must reach the mast cells in advance of the allergen. They are of very little use if taken after the allergic reaction has begun.
For those who are taking cromoglycate-type drugs on a regular schedule, several times a day, it is very important to be conscientious about taking them on time. This maintains the protective effect of the drug, without any gaps.
If you are using these drugs on an ‘as-needed’ basis, you should take them 30 minutes before an allergen is encountered. or 30 minutes before a bout of exercise, if they are being prescribed for exercise-induced asthma. (Note that children sometimes respond differently, getting protection from these drugs immediately.)
The effect of these drugs takes time to build up. You should take them regularly for at least four weeks before deciding whether they are helping you or not.
One point in favour of cromoglycate-type drugs is that they are extremely safe, with few or no side effects in most people. Sadly, they do not work for everyone. A fairly high percentage of children respond well to them, but the response rate is much lower for adults. Nevertheless, adult allergy sufferers, especially those who need steroids to control their symptoms, should always be given the opportunity to try out these drugs. When cromoglycate-type drugs do work, they are very effective and almost always trouble-free, so they are a good alternative to steroids.
Both sodium cromoglycate and nedocromil sodium are available in inhaler form for asthma (see p. 157). Sodium cromoglycate is also available as nose drops for hayfever and other nasal allergies.
All three drugs are available as eye drops. Recent evidence suggests that sodium cromoglycate drops are less effective than the other two, particularly for the treatment of severe allergic conjunctivitis (inflammation of the eye).
Sodium cromoglycate is available in capsule form for food allergy. Note that these capsules are of very limited value in food allergy, and are certainly not a substitute for food avoidance. They do reduce sensitivity a little and can sometimes be helpful for those with multiple food allergies (see p. 67).
Side effects
There are no serious side effects at all for nedocromil sodium. cromoglycate can, very rarely, cause joint pain and swelling. An allergic reaction to the drug itself is even more uncommon. Stop taking the drug and see your doctor promptly if either of these occurs.
The only other side effects that have occasionally been reported are headache, nausea and vomiting. None of these indicates any damaging effect by the drugs – they are all minor side effects.
Eye drops containing these drugs may cause stinging and burning when inserted, but this is a minor side effect and usually wears off. Flushing and dizziness have sometimes been reported with lodoxamide eye drops.
Nose drops may also cause local irritation. This could be due to the drug itself, in which case it is a minor side effect. Alternatively, the irritation may be due to the preservative used or some other non-drug ingredient (see box on p. 33).
Occasionally cromoglycate nose drops cause bronchospasm – contraction of the airway muscles – but this tends to wear off quite quickly. Bronchospasm can also occur when cromoglycate-type drugs are inhaled (see p. 157).
Anti - leu kotriene drugs
These drugs, which have a set of very specific effects (see p. 159), were originally designed to treat asthma. Their potential for treating other allergic diseases is currently being explored:
•    Several studies show that they work well for perennial allergic rhinitis brought on by allergens such as house-dust mite. They also have some effect on hayfever, but standard treatment (such as antihistamines plus a steroid spray for the nose) is more effective.
•    They are especially useful for both rhinitis and asthma in patients suffering from triad (see box on p. 28). Research shows that they also reduce asthmatic reactions to very small test doses of aspirin, but they don’t give protection against anaphylaxis brought on by normal doses.
•    They have also been used successfully in cases of chronic urticaria and for some patients with delayed pressure urticaria. It seems plausible that they would also be helpful for chronic urticarla linked to aspirin sensitivity.
•    Preliminary trials suggest that these drugs might be useful in atopic eczema. Some studies show a very good response that allows a reduction in steroid creams.
•    Montelukast works very well for eosinophilic gastroenteritis and eosinophilic oesophagitis (see p. 72), according to some new studies.
For side effects of these drugs see pp. 159-60.
Anti-IgE drugs
Since the antibody IgE (see box on p. 12) is such a crucial player in allergic reactions, developing drugs that disable this antibody should help allergy sufferers. The first such drug is omalizumab (brand name Xolair) which was licensed for use in the United States in 2003. It is expected to become available in Britain some time in the next few years.
Omalizumab binds to IgE antibodies and stops them from interacting with mast cells, so blocking any allergic reaction. The drug is given as a ‘depot injection’, just under the skin, every 2-4 weeks. It is gradually released from the injection site and moves around the body in the blood, mopping up IgE molecules.
At present, omalizumab is used for severe hayfever and for people with asthma who are not responding well to the usual treatments. It is only worth using if there is clear evidence that allergies play a part in the asthma. Patients who use omalizumab are often able to reduce their dose of inhaled steroids – and they suffer fewer serious asthma attacks and have better lung function. Some patients can even stop using steroids completely.
Other anti-IgE drugs are in the pipeline. Pilot studies show that one works very well for peanut allergy: after just four injections, sensitivity to the allergen falls sharply, reducing the risk of anaphylaxis from traces of peanut eaten accidentally.
More powerful anti-allergy drugs
Occasionally people with severe allergies, who are on constant high doses of steroid tablets, or who fail to respond to steroids, need treatment with powerful anti-inflammatory drugs, such as methotrexate or cyclosporin. These suppress the immune system, and extremely careful monitoring for side effects is needed.
Adrenaline (epinephrine)
Anyone who has suffered anaphylactic shock (see p. 58) should be carrying a special syringe, called an auto-injector, loaded with adrenaline. The injector is very simple to operate and is designed for emergencies. Most allergy sufferers, even children, can give themselves the injection – or a parent or other adult can give it.
Some asthmatics, and those with food allergy who suffer swelling of the throat, may be given adrenaline in inhaler form as well (see pp. 155-6). This can be useful as an additional treatment but it’s definitely not a substitute for an injector.
See pp. 98-9 for instructions on using adrenaline in a crisis.
Wherever you go, take your injector with you. Always keep it close at hand: you need to be able to use it within minutes of the allergic reaction starting. You may be unable to speak (and therefore unable to ask someone else to fetch it) quite soon after the attack begins. The injector must never be refrigerated. It can also be damaged by sunlight and excess heat.
If you live in the countryside or in an area with a poor ambulance sevice, or if you are going camping or hiking somewhere remote, ask your doctor for a second injector, or one that can deliver multiple injections. Also ask about the maximum number of injections that can be given, and never exceed this total. Some doctors believe everyone should have two injectors, just in case the first dose doesn’t do the trick and help is slow in coming.
It is vital that you are shown exactly how to use the auto-injector. Canadian researchers discovered that only one in four
Some common brand names
Common brand names of adrenaline preparations include: auto-injectors – Anapen, EpiPen
inhalers – AsthmaHaler Mist, Bronkaid, Epiphrine
health professionals got the technique correct when demonstrating how to use an auto-injector In this study, pharmacists were much the best as regards accurate instructions. Dummy injectors are useful for training purposes and most pharmacies have them.
When the adrenaline auto-injectors expire, they can be very useful for practising with, or for showing a new baby-sitter or teacher – practise on an orange or grapefruit.
If you are taking beta-blockers (e.g. for a heart condition or anxiety), adrenaline may not have much effect.
Heavy daily use of beta-2 relievers for asthma (see p. 152) will also make adrenaline less effective when you need it.
Side effects
The important side effects of adrenaline involve the heart. Anyone with a heart condition should be given special advice in advance by their doctor about using adrenaline. The same goes for people with diabetes, hyperthyroidism or high blood pressure, and anyone taking tricyclic anti-depressants. There are quite a few minor side effects from adrenaline, such as anxiety, trembling, nausea. sweating, dizziness and cold extremities. These soon wear off.
Drugs that can make you worse
Aspirin and its relatives have a very bad effect on some people with rhinitis and/or asthma (see box on p. 151). Unfortunately, recent research shows that paracetamol is not safe either. It makes asthma more likely to develop in those who do not yet have the disease, and increases the severity of asthma symptoms for those who do. Unlike aspirin, paracetamol affects everyone, because it lowers the levels of a natural antioxidant, called glutathione, which the body makes to protect the lungs from oxidants. The greatest effects are seen in people who take paracetamol regularly (once a week or more), but even an occasional dose makes some difference.
All the other drugs that can make you worse are prescription drugs, and your doctor should be alert to the dangers. But doctors are overworked and sometimes forget, so it is sensible to know about the risks for yourself. If you have any doubt about the drugs you are taking, ask a pharmacist.
Beta-blockers are a major hazard for people with allergies. They can make the airways contract, and can bring on a serious asthma attack. They also make anaphylaxis more likely in someone who already has allergic reactions (see p. 59) and they increase the risk of a severe reaction to
immunotherapy (see p. 166) or skin-prick tests (see p. 91). Beta-blockers are prescribed for high blood pressure, angina and other heart problems, migraine and thyroid disease. There are alternative drugs in all cases. Sometimes asthma develops in people who have been taking beta-blockers for years. The beta-blockers are not responsible for this, but once asthma has begun, they will make symptoms worse. Eye drops for the treatment of glaucoma may also contain beta-blockers and can have a bad effect on asthmatics.
ACE inhibitors, used for heart conditions, may cause a cough and airway narrowing. They may also increase the risk of a severe reaction to immunotherapy.
Female hormones affect asthmatics, so taking the contraceptive pill or hormone replacement therapy (HRT) may make asthma worse. Progesterone-only contraceptive pills tend to cause fewer problems.
The drug isoniazid (INH), prescribed for tuberculosis, makes the body far more susceptible to histamine in foods (see p. 200).
An allergic reaction to a specific drug (e.g. penicillin) can also occur in some people, resulting in urticaria, or even anaphylactic shock.
Aspirin sensitivity
Aspirin sensitivity is not an allergic reaction, because neither IgE nor mast cells are involved. What causes this problem is a metabolic abnormality — a malfunction in one aspect of the body’s chemistry. The details of this are very complicated: you may want to skip the next three paragraphs and
simply read about how to cope with the problem.
The exact nature of aspirin sensitivity is still far from clear, but it seems to involve a relatively poor production of prostaglandins, combined with a plentiful production of leukotrienes. Both these substances are messenger chemicals which, broadly speaking, promote inflammation. But the details of their pro-inflammatory activities differ. It seems that, ideally, the body should have a harmonious balance between the two, and an imbalance produces problems.
Both prostaglandins and leukotrienes are manufactured from certain fats that are found in the diet. These fats, the raw materials, are worked on initially by two different enzymes — one that leads to the production of prostaglandins and another that leads to the production of leukotrienes.
If one of these enzymes is defective, it may mean that the other is oversupplied with raw materials, resulting in a serious imbalance between prostaglandins and leukotrienes. In those with aspirin sensitivity, or at risk of developing aspirin sensitivity, the enzyme that produces prostaglandins seems to be defective.
Even in the absence of aspirin, this imbalance in the production of prostaglandins and leukotrienes causes problems. It leads to symptoms such as chronic urticaria (see p. 51) or rhinitis, nasal polyps and asthma (a cluster of symptoms that is commonly called triad — see box on p. 28).
Taking aspirin can make the imbalance between prostaglandins and leukotrienes even worse in a person with this underlying abnormality. Aspirin exerts its painkilling effects by disabling the main prostaglandin-making enzyme — the enzyme that is already defective.
When someone with aspirin sensitivity takes aspirin, they may suffer worsening asthma, a severe asthma attack or — the worst-case scenario —collapse. This is a potentially fatal reaction, similar to anaphylaxis, requiring emergency medical treatment (see p. 101).
The greatest puzzle about aspirin sensitivity is why it often takes so long to develop in someone who already has the symptoms of triad —indicating the basic metabolic abnormality. It may be as much as 20 years from when someone has their first triad symptoms to when they begin reacting badly to aspirin.
If you have triad symptoms already, but no aspirin sensitivity yet, what should you do? Unfortunately, there are no safe tests for aspirin sensitivity at present — taking a small dose of aspirin and seeing what happens is very hazardous. It is probably best to assume that you are going to become sensitive to aspirin at some stage, and avoid all aspirin and aspirin-like drugs. Caution is the best plan here because aspirin sensitivity can come on very suddenly, and be life-threatening the very first time it occurs. Note
that some triad sufferers have polyps and rhinitis but no asthma until they actually develop aspirin sensitivity — a dose of aspirin suddenly brings on their first asthma attack plus other symptoms of aspirin sensitivity.
Avoiding aspirin itself is not difficult, but aspirin-like drugs pose more of a problem. Every year there are a number of deaths from these drugs. Some cases occur because a busy doctor momentarily forgets that a patient should not take these drugs. The drugs that need to be avoided are all known as non-steroidal anti-inflammatory drugs (NSAIDs), COX-1 inhibitors or COX-2 inhibitors. However you will not see any of these names on the packet. These drugs are very widely used for pain relief (e.g. in headache and backache remedies such as Nurofen), for the treatment of arthritis, and for several other inflammatory diseases.
There are dozens of non-steroidal anti-inflammatory drugs available, and many are sold under several different brand names. The list grows every year, as new drugs or new brands are launched. The only way to avoid these drugs is to be very cautious:
•    When buying any cold- or flu-remedies, painkillers, medicines for sprains or sports injuries (including those you apply directly to the skin), headache tablets or migraine tablets, always buy them at a chemist’s shop rather than a supermarket, and check with the pharmacist that they do not contain aspirin or aspirin-like drugs.
•    Be cautious also about remedies for an upset stomach. A few (e.g. Alka-Seltzer) contain aspirin.
•    Don’t take any drugs unless you are 100% sure of what they contain. Remember that the ingredients of a familiar brand name can sometimes change — read the label every time.
•    When a doctor prescribes any new drug, always mention that you are sensitive to aspirin, or that you have triad symptoms. Alternatively, check with the pharmacist when the prescription is filled.
•    Aspirin-free painkillers almost always contain paracetamol, a drug which can cause a severe reaction (similar to the collapse induced by aspirin itself) in about 5% of those with aspirin sensitivity. If you are taking paracetamol for the first time, start with half a tablet. Be sure that, for the next 2-3 hours, you have a way of getting to hospital quickly should you start to feel ill. (Note that paracetamol has another entirely separate effect, increasing the severity of asthma, and it is best not to take it too often — see box on p. 150.)
Avoiding all aspirin-like drugs will prevent you having anaphylaxis or severe attacks of asthma. Unfortunately, triad symptoms will not go away however careful you are about avoiding aspirin.
It is well worth trying the new anti-leukotriene drugs (see p. 149), especially if you have aspirin-induced asthma. They seem to help with triad symptoms by curtailing the activities of leukotrienes and so redressing the balance between leukotrienes and prostaglandins.

Antihistamines and Allergy

Antihistamines were first introduced in 1947, and are very widely used, so their safety — at least in the case of the older antihistamines — is beyond doubt. Most of the antihistamines have no major ill effects, and no one should feel concerned about taking them. At worst they produce some rather annoying minor side effects, such as drowsiness, which often wear off in time.

These drugs are particularly valuable for hayfever and other allergies in the nose (perennial allergic rhinitis). They are also used for chronic urticaria, sometimes in combination with anotherhistamine-blocking drug — see p. 53.

Antihistamines are not much used for asthma. They have relatively little effect, probably because so many other messenger chemicals are involved in an asthma attack. However, doctors in Japan do use antihistamines for asthma, and it is possible that people of Asiatic origin react differently to them.

Only one antihistamine, ketotifen, is widely used for asthma in the West, and this has other effects besides blocking histamine (see p. 159). A new role may soon develop for antihistamines in thetreatment of asthma, combined with anti-leukotriene drugs (see p. 159).

If you suffer from anaphylaxis you might be given antihistamines in a liquid or chewable form, for use in an emergency. These are not enough in themselves to treat this dangerous condition - you must have an adrenaline injector (see p. 150).

In the past, some doctors prescribed antihistamines for atopic eczema, mainly for their sedative effect(see p. 139) which was thought to help children to sleep better and scratch less at night. This treatment has largely gone out of favour, because its value is in doubt. But a recent study has revealed that the non-sedating antihistamine cetirizine may be useful for very young children with atopic eczema, not only in treating their skin, but also in reducing the chance of them developing asthma (see p. 249).

Most people take their antihistamines in tablet or capsule form. Syrups and sugar-free elixirs areavailable for children.

Antihistamines can also be applied directly, in the form of nasal sprays or eye drops. These are mainlyused to treat hayfever and the conjunctivitis (inflammation of the eye) which often accompanies it.Levocabastine (brand name Livostin) is particularly effective for the eyes.

Antihistamine creams are also sold, without prescription, for the treatment of insect bites - i.e. thenormal non-allergic reaction to such bites. These creams are not recommended for atopic eczema or otherallergic conditions affecting the skin. Not only are they unlikely to help, but they may make mattersworse because, with regular use, skin sensitisation to the antihistamine occurs very readily (see pp.54-5).
Some common brand names

Common brand names include: non-sedating antihistamines - Clarityn, Semprex, Zirtek; Mistamine, Mizollen, Telfast, Terfenadine. Thefirst three are available without prescription.

older (sedating) antihistamines — Atarax, Dimotane, Optimine, Periactin, Piriton, Tavegil, Vallergan eye drops — Emadine, Livostin, Optilast nasal sprays — Livostin, Rhinolast

How antihistamines work
Of the messenger chemicals released when an allergic reaction occurs, the most important is histamine.

This does its work by attaching to specialised receptors in certain parts of the body, and so

triggering various reactions (see box on p. 12). The action of antihistamines is very simple: they bind

to the same receptors as histamine, but they do not trigger any reaction. Histamine cannot bind to the

receptor because the antihistamine is already there.
Unfortunately, the reverse is also true: if the histamine is already there, the antihistamine cannot

elbow it off the receptor, which is why it is important to take the antihistamine well before the

allergen is encountered. Taking antihistamines at the first sign of a snuffle or itch can also work,

but the effects will not be nearly as good as taking them in anticipation of an exposure.
The best approach to treating hayfever, for example, is to start taking the antihistamines at least a

week before the pollen season begins, and preferably two to three weeks before. You should then take

them continuously until it is over. This will make a huge difference to the degree of symptom control

you achieve.
Side effects
The older types of antihistamine, such as chlorphenamine (brand name, Rriton) are relatively

non-specific in their effects – they bind to several different kinds of receptors, not just those for

histamine. As a result they can have some unwanted effects, such as causing drowsiness and poor

coordination. While these sedative effects are no cause for concern in themselves, they can, of course,

be hazardous if you work with dangerous machinery or drive. Avoid both until you are sure how you react

to the antihistamine. Note that the effects of alcohol may be increased.
Very occasionally antihistamines have the opposite effect, causing stimulation rather than sedation;

this is most likely to occur in children and old people. Lowering the dose may solve the problem.
The other possible side effects of the older antihistamines –all of which are minor ones – are

headache, dry mouth, blurred vision, difficulty in passing urine, nervousness, shaky hands, upset

stomach or diarrhoea. A few men suffer impotence while taking antihistamines, but this disappears when

the drug is stopped.
The minor side effects of antihistamines, including drowsiness, often wear off after a while, although

the benefits of the drug remain. So it is worthwhile persisting with an antihistamine, even if it

causes some problems at first. Many people experience side effects from certain antihistamines but not

from others, so try several different types to find one that suits you.
The problem of drowsiness has been reduced, in recent years, thanks to the development of new drugs

that are far more
specific for histamine receptors, the non-sedating antihistamines. A few people do get drowsy even with

these drugs. Again, the effects vary from one drug to another, so if the first one disagrees with you,

try a different one.
It is worth noting – since some people may still have the odd packet in their medicine cabinet – that

two of the non-sedating antihistamines that were available without prescription a few years ago proved

to be unsafe for a small minority of people. One was astemizole (brand names: Hismanal, Pollon-eze),

which has now been withdrawn from use altogether in Britain. The other was terfenadine (brand names:

Triludan, Seldane, Terfenadine) which is still available, but only on prescription.
There are several special precautions relating to terfenadine:
• Never exceed the correct dose.
• If you have ever had any kind of heart problem, talk to your doctor before taking terfenadine.
• Stop taking the drug if you have palpitations, or if you feel faint; see your doctor promptly.
• Do not take terfenadine if you are taking the antibiotic erythromycin, or anti-fungal drugs

such as ketoconazole (Nizoral) or fluconazole (Diflucan), used to treat vaginal thrush.
• Do not take terfenadine if you have liver disease.
• Do not drink grapefruit juice while taking terfenadine: something found naturally in grapefruit

interacts unpleasantly with this antihistamine.
In addition to these special precautions concerning terfenadine, any antihistamine should be treated

with caution by those suffering from epilepsy, Parkinson’s disease, glaucoma, prostate enlargement,

kidney problems, urinary retention, a gastric ulcer, a thyroid disorder, porphyria or liver disease.

Check with your doctor before taking antihistamines if you have any of these conditions.
It may be inadvisable to use antihistamines if you are taking sleeping tablets, anti-depressants or

anti-anxiety drugs – again, see your doctor.
Stop taking antihistamines if you suffer any unusual kind of rash, or if your skin becomes more

sensitive to sunlight.
If you are breast-feeding, note that, because they go through into the milk, the older antihistamines

may make the baby sleepy. However, they do no harm.
Rescue treatment
Most antihistamines perform very badly if you take them once the allergic reaction has set in, but

acrivastine (Semprex) can be good in these circumstances and is non-sedating. No prescription is

required for this drug.
possibly identify all major side effects. We vary in our response to drugs, because we are all so

different at the chemical and cellular level. A drug might have a serious side effect that only affects

one person in 10,000, and no safety trial can hope to identify such a rare response. Only when a drug

is released, and becomes widely used, do such side effects come to light. Other unanticipated side

effects can sometimes arise when people taking the new drug are much older than those in the safety

trials, or belong to a different ethnic group with different susceptibilities. Combining the drug with

certain other drugs can also be a potential source of trouble, although pharmaceutical experts can

often predict such problems from a detailed knowledge of the chemistry of drugs and how they are broken

down in the body. Side effects that take several years to develop - more than the timespan of most

safety trials - will also fail to show up until the drug has been released.
All this may sound very alarming, but in fact severe reactions to new drugs are not that common. And

there are various safety nets in place - doctors keep a close eye on patients taking new drugs, and a

special reporting system ensures that, if unexpected side effects do show up, the information is

quickly shared with others in the medical community.
In order to relate the information here to a particular medicine that you take, you need to know what

drug category it belongs to. Does your inhaler contain a beta-2 reliever, a steroid, a cromoglycatetype

drug or an anti-cholinergic, for example? If you are not sure, ask your pharmacist.
Those are the category names for drugs: they denote families of drugs which are similar chemically
and work in roughly the same way. Within each category, or family, there are a number of individual

drugs. The individual drugs should, ideally, have a standard internationally agreed name - this is

known as the generic name. Unfortunately, a few of the drugs used for allergies and asthma have more

than one generic name - salbutamol is known as albuterol in some parts of the world, and adrenaline is called epinephrine.

Finally there are the brand names, which are the ones most patients are familiar with. These are always

shown with a capital letter, unlike the generic names. Long-established drugs are usually made by

several different pharmaceutical companies, and therefore marketed under several different brand names.

A newer drug, which is still covered by the patent of the pharmaceutical company that developed it,

will be sold under only one brand name.

The issue of brand names is important, because a different brand name might make you think you are taking a different drug, when in fact it is exactly the same drug being marketed in a different guise.If you have suffered side effects from a particular drug in the past, and wish to avoid it in future, take note of its generic name, rather than its brand name. Sometimes the generic name is used as the brand name, in what are called generic drugs. These arerelatively inexpensive copies of popular drug brands -they are just the same chemically, but they costless because there is no advertising of the brand to doctors, and profit margins have been cut to aminimum. In order to reduce National Health Service costs, doctors are now asked to prescribe generic drugs whenever possible.