Posts Tagged ‘toxicity’

Generic Name
Clonidine (KLAH-nih-dene)
Brand Names
Catapres-TTS-2
Catapres-TTS-1    Catapres-TTS-3
Type of Drug
Alpha receptor stimulant.
Prescribed For
High blood pressure, including hypertensive emergency (diastolic blood pressure over 120); also used for excess sweating, childhood growth delay, attention-deficit hyperactivity disorder (ADHD), Tourette’s syndrome, restless leg syndrome, schizophrenic psychosis, migraine, ulcerative colitis, painful or difficult menstruation, hot flashes related to menopause, diagnosis of pheochromocytoma (adrenal-gland tumor), kidney poisoning associated with cyclosporine, diabetic diarrhea, smoking cessation, methadone and opiate detoxification, withdrawal from alcohol and benzodiazepines such as Valium, nerve pain following herpes attack, and allergic reactions in the presence of asthma triggered by external sources.
General Information
Clonidine stimulates nerve endings in the brain called alphaadrenergic receptors. It reduces blood pressure by dilating (widening) blood vessels. Clonidine works quickly, decreasing blood pressure within 1 hour. The other uses of clonidine relate to its stimulation of alpha receptors in the body.
Cautions and Warnings
Do not take clonidine if you are allergic or sensitive to any of its ingredients.
People who have had a stroke or recent heart attack or who have cardiac insufficiency or chronic kidney failure should avoid taking clonidine.
Some people develop a tolerance of their clonidine dosage. If this happens, your blood pressure may increase and your doctor may prescribe a higher dose.
Never stop taking clonidine without your doctor’s knowledge. If you abruptly stop taking clonidine, you may experience an unusual increase in blood pressure accompanied by agitation, headache, nervousness, and severe reactions, possibly death. Restarting clonidine therapy or taking another antihypertensive can reverse these effects.
Clonidine may cause degeneration of the    See your eye doctor for regular GheCk Ups lfiyou are taking this drug.
); you require surgery, your doctor will continue your clonidine therapy until about 4 hours before surgery and resume it as soon as possible afterward.
People who develop skin sensitivity (symptoms include rash, itching, and swelling) to Catapres-TTS, the transdermal patch form of clonidine, may experience the same reactions with oral clonidine.
Possible Side Effects
Tablets
♦    Most common: dry mouth, drowsiness, dizziness, constipation, and sedation.
♦    Common: headache and fatigue. These effects tend to diminish within 4-6 weeks.
•    Less common: appetite loss, swelling or pain in the glands of the throat, nausea, vomiting, weight gain, blood-sugar elevation, breast pain or enlargement, worsening of congestive heart failure, heart palpitations, rapid heartbeat, painful blood-vessel spasm, abnormal heart rhythms, electrocardiogram changes, feeling unwell, changes in dream patterns, nightmares, difficulty sleeping, hallucinations, delirium, anxiety, depression, nervousness, restlessness, rash, hives, thinning or loss of scalp hair, difficult or painful urination, nighttime urination, retaining urine, decrease or loss of sex drive, weakness, muscle or joint pain, leg cramps, increased alcohol sensitivity, dryness and burning of the eyes, dry nose, loss of color, and fever.
Transdermal Patch
✓    Most common: dry mouth and drowsiness.
✓    Less common: constipation, nausea, changes in sense of taste, dry throat, fatigue, headache, lethargy, changes in sleep patterns, nervousness, dizziness, impotence, sexual difficulties, and mild skin reactions including itching, swelling, contact dermatitis, discoloration, burning, peeling, throbbing, white patches, and generalized rash. Rashes of the face and tongue have also occurred but cannot be specifically tied to transdermal clonidine.
Drug Interactions
•    Combining clonidine and a beta-adrenergic blocker may increase the severity of a drug-withdrawal reaction and rebound high MW pressure. This reaction may be very serious.
•    Combining verapamil and clonidine may lead to very low blood pressure and atrioventricular (AV) block (abnormality in heartbeat patterns). This reaction may be very serious.
O    Avoid alcohol, barbiturates, and sedatives because they increase the depressive effects of clonidine.
•    Tricyclic and other antidepressants, appetite suppressants, estrogens, stimulants, indomethacin and other nonsteroidal anti-inflammatory drugs (NSAIDs), and prazosin may counteract the effects of clonidine.
•    clonidine may reduce the therapeutic effects of levadopa +
carbidopa.
Food Interactions
The tablets are best taken on an empty stomach but may be taken with food if they upset your stomach.
Usual Dose
Tablets
Adult: high blood pressure-100 mcg twice a day to start; may be raised by 100 mcg a day until maximum control is achieved. Take no more than 2400 mcg a day. Other uses-100-goo mcg a day, or up to 0.8 mcg per lb. of body weight in divided doses. Seniors should start with a lower dose and increase more slowly.
Child: 50-400 mcg orally twice a day.
Transdermal Patch
Adult: 100 mcg delivered daily from a patch applied once every 7 days. Up to two 300-mcg patches may be needed to control blood pressure. Transdermal dosage exceeding 600 mcg a day has not been shown to increase effectiveness.
Child: not recommended.
Overdosage
Symptoms of overdose are slow heartbeat, central- nervous-system depression, very slow breathing, low body temperature, pinpoint pupils, seizures, lethargy, agitation, irritability, nausea, vomiting, abnormal heart rhythms, mild increases in blood pressure followed by a rapid drop in blood pressure, dizziness, weakness, loss of reflexes, and vomiting. Victims should be taken to a hospital emergency room immediately. ALWAYS bring the prescription bottle or container.
Special Information
Gk’3t1161)e causes drowsiness in about 1/3 of people who take it. Be extremely careful while driving or performing any task that requires concentration. This effect is prominent during the first few weeks of clonidine therapy and then tends to decrease.
Do not take over-the-counter cough and cold medications unless directed by your doctor.
Call your doctor it you become depressed or have vivid dreams or nightmares while taking clonidine, or if you develop swelling in your feet or legs, paleness or coldness in your fingertips or toes, or any persistent or bothersome side effect.
Apply the transdermal patch to a hairless area of skin such as the upper arm or torso. Use a different skin site each time. If the patch becomes loose, apply the supplied adhesive directly over it. If the patch falls off before 7 days are up, apply a new one. Do not remove the patch while bathing.
If you forget a dose of oral clonidine, take it as soon as possible and then go back to your regular schedule. If you miss 2 or more consecutive doses, consult your doctor; missed doses may cause blood pressure increases and severe adverse effects. Do not take a double dose.
Special Populations
Pregnancy/Breast-feeding: Clonidine passes into the fetal bloodstream. Animal studies show that clonidine may damage the fetus in doses as low as 1/3 the maximum dose. When this drug is considered crucial by your doctor, its potential benefits must be carefully weighed against its risks.
Clonidine passes into breast milk. Nursing mothers who must take this drug should use infant formula.
Seniors: Seniors are more susceptible to the effects of this drug and should begin with lower doses.

Generic Name
Clopidogrel (kloe-PID-oe-grel) nQ
Brand Name  Plavix
Type lul Drug Antiplatelet.
Prescribed For
Heart attack and stroke prevention; also used for blood thinning after placement of a vascular stent.
General Information
Artery-clogging blood clots are often the cause of heart attacks and strokes. clopidogrel reduces the risk of both by helping prevent blood-clot formation. This drug thins the blood by making platelets—the cells that aggregate to form clots—less “sticky.” It starts working in as little as 2 hours after taking a single tablet. The drug’s blood-thinning effect lasts until inactivated platelets are replaced by the body. Studies suggest that clopidogrel is more effective than aspirin in preventing heart attack and stroke in people at risk. People taking clopidogrel after scent surgery usually take it for a relatively short period. Those taking it to prevent a heart attack or stroke must take it for life.
Cautions and Warnings
Do not take clopidogrel if you are allergic or sensitive to any of its ingredients or to ticlopidine, a related antiplatelet. These drugs can rarely cause a rapid drop in white-blood-cell count.
People with bleeding ulcers, brain hemorrhages, or other bleeding problems should use clopidogrel with caution.
Thrombotic thrombocytopenic purpura (TTP) is a rare but serious complication of clopidogrel, sometimes reported after less than 2 weeks of treatment. See your doctor right away if you develop a sudden fever, unusual bruising, nosebleeds, bleeding gums, or any other unusual symptoms. TTP reduces your platelet count, interfering with blood clotting, and affects white-blood-cell count.
People with liver problems should use clopidogrel with caution.
Possible Side Effects
✓    Most common: rash and other skin problems.
✓    Common: chest pain, accidents, flu-like symptoms, pain, headache, dizziness, abdominal pain, upset stomach, joint pain, back pain, black-and-blue marks, and respiratory infection.
✓    Less common: tiredness, Swollen arms or legs, high blood pressure, diarrhea, nausea, bleeding, nosebleeds, breathing difficulties, runny nose, coughing, bronchitis, high blood cholesterol, urinary infection, and depression.
✓    Rare: bleeding in the brain and stomach ulcer. Contact your doctor if you experience any side effect not listed above.
Drug Interactions
•    Clopidogrel may interfere with the body’s ability to break down fluvastatin, nonsteroidal anti-inflammatory drugs (NSAIDs), phenytoin, tamoxifen, tolbutamide, torsamide, and
warfann.
•    Combining clopidogrel and NSAIDs may increase blood loss and bleeding in the stomach and intestines.
•    Do not combine clopidogrel and other antiplatelet drugs or
the anticoagulant (blood thinner) warfarin unless you are
under your doctor’s direct supervision. This interaction may
prevent normal blood clotting and lead to severe bleeding
problems.
Food Interactions
Clopidogrel may be taken without regard to food or meals.
Usual Dose
Adult: 75 mg a day.
Overdosage
Little is known about the effects of clopidogrel overdose aside from reduced blood clotting. Overdose victims should be taken to a hospital emergency room. ALWAYS bring the prescription bottle or container.
Special Information
Minor cuts may take longer to stop bleeding during treatment with clopidogrel. If you are having surgery, make sure your doctor knows you are taking clopidogrel. You may have to stop taking the drug I week before surgery.
If you forget a dose, 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.
Special Populations
Pregnancy/Breast-feeding: The safety of using clopidogrel during pregnancy is not known. Other antiplatelet drugs, tike aspirin, are not used during pregnancy due to their possible effects on Mrjlher and fetus. When this drug is considered crucial by your doctor, its benefits must be carefully weighed against its risks.
Clopidogrel may pass into breast milk. Nursing mothers who must take this drug should use infant formula.
Seniors: Seniors may take this drug without special precaution.

Generic Name
Clorazepate (klor-AZ-uh-pate) 99
Brand Names
Gen-Xene    Tranxene-SD
Tranxene    Tranxene T-Tab
Type of Drug
Benzodiazepine sedative.
Prescribed For
Anxiety, tension, fatigue, and agitation; symptoms of acute alcohol withdrawal; partial seizures; also prescribed for irritable bowel syndrome and panic attacks.
General Information
Clorazepate dipotassium is a benzodiazepine. Benzodiazepines directly affect the brain. They can relax you and make you more tranquil or sleepier, or they can slow nervous system transmissions in such a way as to act as an anticonvulsant. Many doctors prefer benzodiazepines to other drugs that can be used to similar effect because they tend to be safer, have fewer side effects, and usually work as well, if not better.
Cautions and Warnings
Do not take clorazepate if you are allergic or sensitive to any of its ingredients or to another benzodiazepine drug, including clonazepam.
Clorazepate can aggravate narrow-angle glaucoma, but you may take it if you have open-angle glaucoma and are receiving therapy for it.
Other conditions in which clorazepate should be avoided are: severe depression, severe lung disease, sleep apnea (intermittent cessation of breathing during sleep), liver disease, drunkenness, and kidney diseaap_, to inOn of these conditions, the qq)NSSvve effects of clorazepate may be enhanced or could be detrimental to your overall condition.
Clorazepate should not be taken by psychotic patients because it is not effective for them and can trigger unusual excitement, stimulation, and rage.
Clorazepate is not intended to be used for more than 3-4 months at a time. Your doctor should reassess your condition before continuing your prescription beyond that time.
Clorazepate may be addictive. It should be used with caution in people with a history of drug dependence.
Drug withdrawal may develop if you stop taking it after as few as 4 weeks of regular use but is more likely after longer use. It may start with anxiety and progress to tingling in the hands or feet, sensitivity to bright light, sleep disturbances, cramps, tremors, muscle tension or twitching, poor concentration, flu-like symptoms, fatigue, appetite loss, sweating, and changes in mental state. Your dosage should always be reduced gradually to prevent drug withdrawal symptoms.
Possible Side Effects
Weakness and confusion may occur, especially in seniors and in those who are more sickly.
✓    Most common: mild drowsiness during the first few days of therapy.
✓    Less common: confusion, depression, lethargy, disorientation, headache, inactivity, slurred speech, stupor, dizziness, tremors, constipation, dry mouth, nausea, inability to control urination, sexual difficulties, irregular menstrual cycle, changes in heart rhythm, low blood pressure, fluid retention, blurred or double vision, itching, rash, hiccups, nervousness, inability to fall asleep, and occasional liver and kidney dysfunction. If you have any of these symptoms, stop taking the medicine and contact your doctor immediately.
✓    Rare: Rare side effects can affect your heart, stomach and intestines, urinary tract, blood, muscles and joints. Contact your doctor if you experience any side effects not listed above.
Drug Interactions
•    Clorazepate is a central-nervous-system depressant. Don’t mix it with alcohol, other sedatives, narcotics, barbiturates, monoamine oxidase inhibitor and other antidepressants, and antihistamines. Taking Clorazepate with these drugs may result in excessive depression, tiredness, sleepiness, breathing difficulties, or related symptoms.
•    Smoking may reduce clorazepate’s effectiveness by in-
creasing the rate at which it is broken down by the body.
•    Clorazepate’s effects may be prolonged when it is mixed with cimetidine, contraceptive drugs, disulfiram, fluoxetine, isoniazid, ketoconazole, metoprolol, probenecid, propoxyphene, propranolol, rifampin, or valproic acid. Theophylline may reduce clorazepate’s sedative effects.
•    If you take antacids, separate them from your clorazepate dose by at least 1 hour to prevent them from interfering with the absorption of clorazepate into the bloodstream.
•    Clorazepate may increase blood levels of digoxin and the chances of digoxin toxicity.
•    The effect of levodopa + carbidopa may be decreased if it is taken together with clorazepate.
•    Combining clorazepate with phenytoin may increase phenytoin blood concentrations and the chances of phenytoin toxicity.
Food Interactions
Clorazepate is best taken on an empty stomach, but it may be taken with food if it upsets your stomach.
Usual Dose
Immediate-Release
Adult and Child (age 9 and over): 15-60 mg daily. The average dose is 30 mg in divided quantities, but dosage must be adjusted to individual response for maximum effect. Maximum recommended daily dose is 90 mg. For treatment of anxiety, clorazepate may be taken as a single dose at bedtime.
Child (under age 9): not recommended.
Sustained-Release
Adult: The sustained-release form of clorazepate may be given as a single dose, either 11.25 or 22.5 mg, once every 24 hours. Sustained-release tablets are not recommended for the initial dosage.
Child: not recommended.
Overdosage
Symptoms of overdose are confusion, sleepiness, poor coordination, lack of response to pain such as a pin prick, loss of reflexes, shallow breathing, low blood pressure, and coma. The victim should be taken to a hospital emergency room. ALWAYS bring the prescription bottle or container.
Special Information
Clorazepate can cause tiredness, drowsiness, inability to concentrate, or similar symptoms. Be careful if you are driving, operating machinery, or performing other activities that require concentration.
People taking clorazepate for more than 3 or 4 months at a time may develop drug withdrawal reactions if the medication is stopped suddenly (see “Cautions and Warnings”). Do not stop taking clorazepate or increase or decrease your dosage without first consulting your doctor.
If you forget a dose of clorazepate, take it as soon as you remember. If it is almost time for your next dose, skip the dose you forgot and continue with your regular schedule. Do not take a double dose.
Special Populations
Pregnancy/Breast-feeding: Clorazepate may cause birth defects if taken during the first 3 months of pregnancy. Avoid this drug if you are or might be pregnant.
Clorazepate may pass into breast milk. Nursing mothers who must take clorazepate should use infant formula.
Seniors: Seniors, especially those with liver or kidney disease, are more sensitive to the effects of clorazepate and generally require smaller doses to achieve the same effect.

Generic Name
Clemastine (KLEH-mas-tene) A
Brand Names
DayHist-1    Tavist-1
Tavist    Tavist Allergy
Combination Pr(3dUtj
Generic Ingredients: Acetaminophen + Clemastine + Pseudoephedrine
Tavist Allergy/Sinus/Headache
Type of Drug  Antihistamine.
Prescribed For
Sneezing, stuffy and runny nose, itchy eyes, and scratchy throat caused by seasonal allergies and for other symptoms of allergies such as rash, itching, and hives.
General Information
Antihistamines generally work by blocking the release of naturally occuring histamine (a chemical released by body tissue during an allergic reaction) from cells at the H, histamine receptor site, drying up secretions of the nose, throat, and eyes. Clemastine fumarate is less sedating than most antihistamines, but not less sedating than astemizole, cetirizine, or loratadine.
Cautions and Warnings
Clemastine should not be taken if you are allergic or sensitive to any of its ingredients.
People with asthma or other deep-breathing problems, heart disease, high blood pressure, diabetes, enlarged prostate, glaucoma, stomach ulcers or other stomach problems, and hyperthyroidism should use clemastine with caution because its side effects can aggravate these problems.
Possible Side Effects
✓    Most common: drowsiness; headache; weakness; nervousness; stomach upset; nausea; vomiting; cough; stuffy nose; diarrhea; constipation; sore throat; nosebleeds; and dry mouth, nose, or throat.
✓    Less common: allergic reaction (symptoms include rash, itching, hives, and breathing difficulties), sleeplessness, menstrual irregularities, muscle aches, sweating, tingling in the hands or feet, frequent urination, visual disturbances, and ringing or buzzing in the ears.
Drug Interactions
•    Cbrnbining clemastine with alcohol, sedatives, sleeping pills, or other nervous system depressants may increase the depressant effects of clemastine. Do not combine these drugs.
•    The effects of oral anticoagulant (blood-thinning) drugs may be decreased by clemastine. Do not take this combination without your doctor’s knowledge.
Monoamine oxidase inhibitor antidepressants may increase the drying and other effects of clemastine. This combination can also worsen urinary difficulties.
e When taking antihistamines on a regular basis, notify your doctor if you are taking large amounts of aspirin. Effects of too much aspirin may be masked by the antihistamine.
Food Interactions
Clemastine is best taken on an empty stomach at least 1 hour before or 2 hours after eating; it may be taken with food if it upsets your stomach.
Usual Dose
Adult and Child (age 12 and over): 1.34 mg twice a day up to 8.04 mg of the syrup or 2.68 mg of the tablets in 24 hours.
Child (age 6-12) (syrup only): 0.67 mg twice a day or up to 4.02 mg a day.
Overdosage
Overdose is likely to cause severe side effects. Overdose victims should be given ipecac syrup—available at any pharmacy—to induce vomiting and should then be taken to a hospital emergency room for treatment. ALWAYS bring the prescription bottle or container.
Special Information
Clemastine may make it difficult for you to concentrate or perform complex tasks such as driving a car. Be sure to report any unusual side effects to your doctor
Antihistamines may occasionally produce excitability, particularly in children.
If you forget to take a dose of clemastine, take it 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
PregnancylBreast-feedj(IV. DO not take any antihistamines without WU ‘Obtlor’s knowledge if you are or might be pregnant—especially during the last 3 months of pregnancy, because newborns may have severe reactions to antihistamines.
Small amounts of clemastine pass into breast milk. Nursing mothers who must take clemastine should use infant formula.
Seniors: Seniors are more sensitive to side effects.

Generic Name
Clindamycin (klin-duh-MYE-sin)
Brand Names
Cleocin    Clindesse
Cleocin T    Clindets
Clinda-Derm    Evoclin Clindagel
Type of Drug  Antibiotic.
Prescribed For
Serious bacterial infections. The vaginal cream is used to treat bacterial vaginosis. Topical clindamycin is used to treat acne and rosacea.
General Information
Clindamycin is one of the few oral drugs that is effective against anaerobic bacteria, which grow only in the absence of oxygen and are often found in infected wounds, lung abscesses, abdominal infections, and infections of the female genital tract. It also works against bacteria usually treated with penicillin or erythromycin, including serious respiratory tract infections. Clindamycin may be useful for treating certain skin or soft tissue infections. It kills the bacteria that frequently cause acne.
Clindamycin is not used to treat vaginal fungus or yeast infections.
Cautions and Warnings
Do not take clindamycin if you are allergic or sensitive to any of its ingredients or to lincomycin, another antibiotic.
People with asthma or a history of allergies should use clindamycin capsules with caution.
Clindamycin can cause a severe intestina(kmkation called colitis, which can be fatal. Signs of colitis are diarrhea, blood in the Stool, and abdominal cramps. Any form of this drug, including products applied to the skin and the vaginal cream, can provoke colitis. Because of this, clindamycin should be reserved for serious infections or those that cannot be treated with other drugs.
Clindamycin should be used with caution if you have gastrointestinal disease or kidney or liver disease.
Possible Side Effects
Capsules
✓    Most common: stomach pain; nausea-, vomiting-, diarrhea,
in up to 20% of people; and pain when swallowing.
♦    Less common: itching; rash; signs of serious drug sensitivity, such as difficulties breathing and yellowing of the skin or the whites of the eyes; colitis, (see “Cautions and Warnings”); effects on blood components; and joint pain.
Topical Lotion
♦    Most common: dry skin, redness, burning, peeling, oily skin, and itching.
♦    Less common: diarrhea, abdominal pain, upset stomach, and colitis (see “Cautions and Warnings”).
Vaginal Cream
♦    Most common: vaginal itching or irritation; thick, white vaginal discharge; and pain during intercourse.
♦    Less common: nausea, vomiting, diarrhea, constipation, abdominal pain, dizziness, headache, vertigo, and colitis (see “Cautions and Warnings”).
Drug Interactions
•    Do not combine clindamycin and erythromycin.
•    The absorption of clindamycin capsules into the bloodstream is delayed by Kaolin-Pectin Suspension (prescribed for diarrhea). Separate these drugs by at least 1 hour.
•    clindamycin should be used with caution by people also using neuromuscular agents.
Food Interactions
Take the oral medication with a full glass of water or with food to prevent irritation of the stomach and intestine.
Usual Dose
Capsules
MUIV ) 50-450 mg every 6 hours.
Child (under age 16): 3.5-11 mg per lb. of body weight a day, in 3-4 doses. For severe infections, at least 37.5 mg 3 times a day, regardless of weight.
Foam: Dispense enough to cover the affected area(s) onto a cool surface (the foam will melt on contact with warm skin). Use fin-gertips to massage small amounts into the affected area(s) until the foam disappears.
Suppositories: Insert 1 suppository a day for 3 consecutive days.
Topical Lotion: Wash the skin and pat dry before application. Apply enough to cover the affected area(s) with a thin coat twice a day.
Vaginal Cream: Insert 1 applicator’s worth at bedtime for 7 consecutive days, except for Clindesse, which requires one applicator’s worth once at any time of day.
Overdosage
clindamycin overdose may lead to severe diarrhea and other drug side effects. Do not treat this diarrhea on your own. Discontinue use of this drug and call your local poison center for information. If you go to an emergency room for treatment, ALWAYS bring the prescription bottle or container.
Special Information
Prolonged or unsupervised use of clindamycin may lead to secondary infections from susceptible organisms. such as fungi. Take this drug for the full course of therapy as indicated by your physician.
If you develop severe diarrhea or abdominal pain, call your doctor at once. Call your doctor immediately if you experience breathing difficulties or jaundice (yellowing of the skin or whites of the eyes).
Women using the vaginal cream should not have vaginal intercourse or use other vaginal products such as tampons or douches until treatment is complete.
Use of latex condoms or diaphragms within 72 hours following treatment with the vaginal creams or suppositories is not recommended. These products may decrease the efficacy of condoms or diaphragms.
The topical lotion is for external use only. Avoid contact with your eyes or mucous membranes.
If you miss a dose of oral clindamycin, take it as soon as you rememlae~. SSW19 almost time for your next dose of clindamycin, double that dose and go back to your regular dosage schedule.
Special Populations
Pregnancy/Breast-feeding: This drug crosses into fetal blood circulation. When the drug is considered crucial by your doctor, its potential benefits must be carefully weighed against its risks.
clindamycin passes into breast milk. Nursing mothers who must take oral clindamycin should use infant formula.
Seniors: Seniors with other illnesses may be unable to tolerate diarrhea and other clindamycin side effects.

Generic Name
Clonazepam (klon-A-zeh-pam)
Brand Name  Klonopin
Type of Drug  Anticonvulsant.
Prescribed For
Petit mal and other seizures and panic attacks; also prescribed for periodic leg movements during sleep, speaking difficulty associated with Parkinson’s disease, acute manic episodes, nerve pain, and schizophrenia.
General Information
Clonazepam is a benzodiazepine drug. Clonazepam is not used as a sedative or hypnotic. It is used only for the uses described above in people who have not responded to other drug treatments. Tolerance to the effects of clonazepam commonly develops within about 3 months of use. Your doctor may raise your clonazepam dosage periodically to maintain the drug’s effect.
Cautions and Warnings
Do not take clonazepam if you are allergic or sensitive to any of its ingredients or any other benzodiazepine.
When stopping clonazepam treatments, the drug must be discontinued gradually. Abrupt discontinuance of clonazepam may lead to drug withdrawal symptoms including severe seizures, tremors, abdominal or muscle cramps, vomiting, whet increased sweating.
IJSIF,l OfMazeparn with caution if you have a chronic respiratory illness, since the drug tends to increase salivation and other respiratory secretions and can make breathing more labored.
Avoid using clonazepam if you have severe depression, severe lung disease, sleep apnea (intermittent cessation of breathing during sleep), liver disease, alcoholism, or kidney disease. These conditions may exacerbate the depressive effects of benzodiazepines, and such effects may be detrimental to your overall
condition.
Clonazepam can aggravate narrow-angle glaucoma, but if you have open-angle glaucoma, you may take it.
Possible Side Effects
♦    Most common: drowsiness, poor muscle control, and behavioral changes.
✓    Rare: Rare side effects can occur in almost any part of the body but are most likely to affect mental function, stomach and intestines, urinary function, blood, and liver. Contact your doctor if you experience any side effect not listed above.
Drug Interactions
•    The depressant effects of clonazepam are increased by sedatives, sleeping pills, narcotic pain relievers, antihistamines, alcohol, monoamine oxidase inhibitor antidepressants, tricyclic antidepressants, and other anticonvulsants.
•    Mixing valproic acid and clonazepam may produce severe petit mal seizures.
•    Smoking, phenobarbital, phenytoin, carbamazapine, and rifampin may reduce clonazepam’s effectiveness.
•    Clonazepam may increase the requirement for other anticonvulsant drugs in people who suffer from multiple types of seizures.
•    The effects of clonazepam may be prolonged when it is taken with cimetidine, contraceptive drugs, disulfiram, fluvoxamine, isoniazid, oral antifungal medications (e.g. ketoconazole), metoprolol, probenecid, propoxyphene, or propranolol.
•    Theophylline may reduce clonazepam’s sedative effects.
•    Separate antacids from y<3kwc_%1Dnazepam dose by at least 1 bZldi %prevent them from interfering with clonazepam being absorbed into the bloodstream.
•    Clonazepam may increase blood levels of digoxin and the risk of digoxin toxicity.
•    Clonazepam may decrease the effect of levodopa + carbidopa.
Food Interactions
Clonazepam is best taken on an empty stomach but may be taken with food if it upsets your stomach.
Usual Dose
Clonazepam is available in either tablets or orally disintegrating tablets, called wafers. Wafers should not be opened until immediately before the dose is to be taken. Do not push the wafer through the foil. Use dry hands to remove the wafer. The wafer will disintegrate quickly in saliva.
Seizures
Adult and Child (age 10 and over): starting dose    0.5 mg 3 times a day. The dose is increased by 0.5-1 mg every 3 days until seizures are controlled or side effects develop. The maximum daily dose is 20 mg.
Panic attacks
Adult and Child (age 10 and over): starting dose-0.25 mg twice daily. The dose is increased to 1 mg a day after 3 days. Most people do not require a higher dose.
Child (under age 10 or below 66 Ms.): starting dose-0.0220.066 mg per lb. of body weight a day in divided doses. Dosage can be increased gradually to a daily dose of 0.22-0.44 mg per lb. of body weight.
Other uses for clonazepam involve doses from 0.5-16 mg a day, depending on the condition and its severity. Clonazepam dosage must be reduced in people with impaired kidney function.
Overdosage
Overdose may cause confusion, coma, poor reflexes, sleepiness, low blood pressure, labored breathing, and other depressive effects. If the overdose is discovered within a few minutes and the victim is still conscious, it may be helpful to induce vomiting with ipecac syrup—available at any pharmacy. Overdose victims must be taken to a hospital emergency room. ALWAYS bring the prescription bottle or contai”iaT.
Special Information
Clonazepam may interfere with your ability to drive or perform other complex tasks because it can cause drowsiness and difficulty in concentrating.
Your doctor should perform periodic blood counts and liver function tests while you are taking this drug to check for possible
side effects.
Do not suddenly stop taking clonazepam—severe seizures may result. The dosage must be discontinued gradually by your doctor.
If you miss a dose by 1 hour or less, take it right away. Otherwise, skip the dose you forgot and go back to your regular schedule. Do not take a double dose.
Carry identification or wear a bracelet indicating that you have a seizure disorder for which you take clonazepam.
Special Populations
Pregnancy/Breast-feeding: Clonazepam crosses into the fetal circulation and can affect the fetus. Women who are or might be pregnant should avoid it. When the drug is considered crucial by your doctor, its potential benefits must be carefully weighed against its risks.
Some reports suggest a strong link between anticonvulsant drugs and birth defects, though most of the information pertains to phenytoin and phenobarbital, not clonazepam. It is also possible that the epileptic condition itself or genetic factors common to people with seizure disorders may figure in the higher incidence of birth defects.
Clonazepam may pass into breast milk. Nursing mothers who must take this drug should use infant formula.
Seniors: Seniors, especially those with liver or kidney disease, are more sensitive to the effects of this drug—especially dizziness and drowsiness—and may require smaller doses.

Notes on dosage
In this dictionary of drugs, the doses, unless otherwise stated, are average daily doses for adults, and are normally given as divided doses at suitable intervals. An indication is given of those few drugs that are taken as a single daily dose, or where
the dose is based on the surface area of the body expressed as square metres (ml).
When a dose range is indicated, a small initial dose is often followed by gradually increasing doses according to need and response, but with long-acting drugs care must be taken to avoid excessive dosage, as such drugs may then accumulate in the body and have toxic side-effects. It should be noted that the side-effects of a drug may prevent the administration of an optimum therapeutic dose, and a recommended dose is often a compromise between activity and toxicity. The gap is sometimes referred to as the ‘therapeutic window’, and the wider the gap the safer the drug.
Dosage is also influenced by the route of administration, as oral doses are normally larger than those given by intramuscular injection, and the latter are in turn larger than those given intravenously. The weight, age and sex of a patient may also have to be taken into account when assessing dosage. Renal and hepatic
-impairment may require an adjustment of dose, whereas if tolerance to a drug
develops, a larger dose may be required to evoke an adequate response. Dosage
also requires particular care during pregnancy if toxic effects on the fetus are to be avoided and, ideally, no drug should be given in pregnancy unless the need outweighs the risks.
Doses for infants also present problems. Their drug-detoxifying enzyme
systems and renal excretory capabilities are not fully developed although,
paradoxically, they have higher metabolic rates than adults, and so may sometimes require an apparently relatively high dose of a drug.

Doses for the elderly also frequently require modification, as their reduced renal efficiency may cause accumulation of the drug and increase susceptibility to toxic effects, unless reduced doses are given. Elderly patients are, in any case, more susceptible to nephrotic drugs generally. Hepatic disease may also increase drug toxicity as liver enzymes play a major part in drug metabolism, and severe liver disease may give rise to a drug toxicity that might not otherwise occur. Hyperlipidaemic drugs, fusidic acid and some antifungal agents of the ketoconazole type are examples of drugs best avoided in hepatic disease. Multiple therapy may also lead to an increased and not always appreciated incidence of drug toxicity. For further information on these important aspects of drug dosage, a book for nurses on drugs and pharmacology should be consulted.

Controlled drugs
Drugs likely to cause dependence and misuse are referred to as ‘controlled drugs’ (CDs), as they are subject to the strict prescription requirements of the Misuse of Drugs Act, 1971, and are distinguished in this book by a dagger t. They include opium, morphine, heroin (diamorphine), pethidine and other synthetic, potent analgesics/narcotics, dihydrocodeine injection, barbiturates (except intravenous anaesthetics) and amphetamines. Controlled drugs can be supplied only on receipt of a hand-written prescription from the prescriber, giving full details of the patient, the drug, the form and strength of the prescription to be dispensed, and the total amount to be supplied expressed in both words and figures. Certain weak preparations of some controlled drugs, such as Kaolin and Morphine Mixture for diarrhoea, with which misuse is unlikely, are exempt from control, and can be obtained without prescription.

suramin A drug used in the early treatment of trypanosomiasis, but it is of no value in the later stages of the disease as it does not enter the cerebrospinal fluid.
Dose: I g i.v. weekly for 5 weeks, after a tolerance test dose of 200 mg. Side-effects are gastrointestinal disturbances, dermatitis, hyperac%thesia and kidney damage.
suxamethonium A short-acting, depolarizing muscle relaxant, with an action lasting 3-5 minutes. A preliminary injection of thiopentoric should first be given, as the initial effect of suxamethonium is a
painful muscle contraction before the relaxant action supervenes.
Dose: 20- tOO ing i.v. during surgery, with further doses according to need. Suxamethonium may also be given as a 0.1% solution by i.v. infusion. Exceptionally, the muscle relaxant action of the drug may be prolonged with marked apnoea. Unlike non-depolarizing muscle relaxants, the action of suxamethonium cannot tie reversed. Severe hepatic disease is a contraindication. (Anectine: Scoline).
sympathomimetics Drugs that have an action similar to adrenaline, and act on both alpha- and beta-adrenoceptors. More selective compounds, such as salbutamol, act on the beta,-adrenoceptors in the lungs and have an increased bronchodilator action. They also relax uterine muscle, and are used to prevent premature labour. Others such as dobutamine and dopamine have a more selective action on the beta,- receptors in the heart, and are referred to as isotropic sympathorninictics.
tacalcitol A vitamin D. derivative used in the treatment of psoriasis as an ointment containing 4 pg/g of the drug. It is applied sparingly once daily at night, and continued as required. Not more than 2 treatments over 8 weeks per year. (Curatoderm).
tacrolimusV A macrolide derivative with marked immunosuppressant properties. It is used in liver and kidney transplantation, and appears to act by suppressing T-cell activation. It may also inhibit the formation of cytotoxic lymphocytes that are concerned
Tel
with graft rejection. See Drug Data Sheet for details of dose and extensive side-effects including neurotoxicity and hypertrophic cirdiomyopathy. (Prograf).
talc A form of magnesium silicate, widely used as a skin dusting powder. It has also been used as a lubricant for surgeons’ gloves, but it may cause a talc granuloma if any reaches the tissues during operation, and glove powders prepared from starch are preferred.
tarnoxifen An oestrogen-receptor
antagonist used mainly in breast cancer, particularly when metastases are present. Dose: 20 mg daily. It is usually well tolerated, but side-effects include hot flushes, dizziness, rash, by
. percalcaciiiia and
an increase in tumour pain. Unlike other oestrogen-antagonists, tamoxifen has no androgenic properties. It has also been used in sonic forms of anovulatory sterility. (Nolvadex). See page 122 an(] Table 8.
tamsulosinV A relatively selective alpha adrenoceptor antagonist. It lowers the tone of bladder and prostatic smooth muscle, and is used in benign prostatic hyperplasia. Dose: 400 mg daily after breakfast with a glass of water. The first dose should be taken in bed to avoid postural hypotension. Other side-effects include palpitations and dizziness and hypotension. (Floniax). See page 164 and Table 28.
tazabactam An inhibitor of betalactamases. It is used in association with some antibiotics to extend the activity against resistant beta - lactamase - producing bacteria. Tazacin is a mixed product containing piperacillin and tazabactam.
tazarotene A retinoid used as an aqueous gel (0.05-0.1 %) in psoriasis. Applied once daily to the affected skin area only. (Zorac).
teicoplanin An antibiotic that acts by interfering with bacterial cell wall development. It has a wide range of activity, but is used mainly in the treatment of severe staphylococcal infections that fail to respond to other antibiotics.
Dose: loo mg initially by i.v. injection, lollowed by 200 nig as a single daily dose, which may be given by i.m. injection. Double doses in severe infections. Side-effects include gastrointestinal disturbances, dizziness, fever and rash (Targocid).

temazepam A mild hypnotic of the nitrazepain type, but with a shorter duration of action. It is useful in the insomnia of the elderly, arid is also of value as a preoperative anxiolytic agent.
Dose: 10-20 ing. Daytime drowsiness is less common than with related drugs. See page 152 and Table 22.
ternocillin A penicillin-type of antibiotic active chiefly against infections due to penicillinase-producing Gram-negative bacteria, with the notable exception of pseudomonas. It is used in respiratory and urinary tract infections due to susceptible organisms.
Dose: 2-4 g daily by injection, but in simple urinary tract infections a single daily dose off g may be effective. (Temopen).
I Tet
inie’tion. (Bricarly]). See page 118 and Table 6.
terfenadine An antihistamine with reduced sedative and other side-effects on the central nervous system. It is effective in hay fever, allergic skin conditions and other allergic states.
Dose: 120 mg daily. Best given alone, as combined use with imidazole antifungal agents or with many other drugs may cause severe reactions. See Drug Data Sheet for details. (Triludan). See page 110 and Table 2.
terlipressin A synthetic form of vasopressin, used to control bleeding from oesophageal varices.
Dose: 1-2 nig i.v., repeated if required 4-6-hourly, (Gl)j)ressin).
tenoxicam A non-steroidal anti-inflamma- tory drug (NSAID) with the actions, uses and side-effects of that group.
Dose: 20 mg as a single daily dose. (Mobillex). See page 105 arid Table 29.
terazocin An alpha-receptor antagonist used in hypertension. It produces a peripheral vasodilation by a blockade of post-synaptic alpha-receptors.
Dose: I mg tit night initially, slowly increase(] up to 10 mg as a single daily dose. Small initial doses are necessary to avoid episodes of syncope during early treatment. Reduced doses are indicated when terazocin is given with thiazide diuretics or other anti-hypertensive agents. Side-effects are dizziness, drowsiness and peripheral oedema. It is also used in benign prostatic hypertrophy.
(I lvpovase). See page 149 arld’I'able 21.
testosterone The androgenic hormone of the testes, which controls the development of the male sex characteristics. It is used mainly in the treatment of hypogonadism
by the i.m. injection of depot preparations    97 of long-acting testosterone derivatives. Subcutaneous implantation of testosterone pellets (200-600 mg) has been used in the treatment of metastatic breast cancer. Side-effects are weight gain, virilism and hypercalcaemia.
tetanus vaccines Preparations of tetanus toxin that has been modified by treatment with formaldehyde. They stimulate the formation of protective antitoxin. They are used for active immunization against tetanus, but for young children a combined diphtheria, pertussis and tetanus vaccine is usually preferred.
terbinafine An antifungal agent that acts by interfering with the synthesis of ergosterol, an essential constituent of fungal cell membranes. It is used in fungal infections of the skin and nails, but it is not effective in pityriasis (Tines versicolor).
Dose: 250 mg daily for 2-6 weeks; half-doses in severe liver or renal impairment. Side-effects are rash, loss of appetite and gastrointestinal disturbances. (I.arnisil).
terbutaline A selective beta-adrenoceptor stimulant and bronchodilator, with the actions, uses and side-effects of salbutamol.
Dose: 7.5-15 mg orally daily, by aerosol inhalation; 250-500 jig by &L, i.rn. or i.v.
tetrabenazine A drug of the haloperidal type, but used mainly in the treatment of Huntington’s chorea and similar disorders of movement.
Dose: 75-200  ing daily. It may cause drowsiness and extra-pyramidal side-effects.
tetracosactrin A synthetic form of corticotrophin.
Dose: it single injection of 250 pg as a test of adrenal cortex function, as after such an injection the level of cortisol in the plasma should rise within an hour. It is also given as single I mg i.m. depot preparation in
the 5-hour diagnostic test. (Synacthen; Synacthen Depot).

tetracycline A wide-range antibiotic very similar both chemically and pharmacologically to chlortetracycline, oxytetracycline, clomocycline, and related compounds referred to generically as the tetracyclines. They all have the same type of action against both Gram-positive and Gram-negative organisms, but exhibit certain differences in solubility, absorption and excretion. These differences are reflected in the different doses, as tetracycline is given in doses of 250 mg 4 times a day, whereas with doxycycline a single daily dose of 100 ing may be adequate. Long treatment with a tetracycline may lead to gastrointestinal disturbance owing to changes in the normal bacterial population of the intestinal tract. The use of the tetracyclines has declined with the emergence of bacterial resistance. They also have the disadvantage of being taken up and staining growing teeth and bone, and so should riot be given to children or used during pregnancy. The absorption of the tetracyclines is reduced by antacids, calcium, iron and milk. See page 249 art(] Table 35.
theophylline A bronchodilator used in the less severe forms of asthma and respiratory disease. (In severe and acute asthma arninophylline is usually preferred.) Dose: 180 nig- I g daily. Side-effects include gastrointestinal disturbances and tachycardia, but are less frequent when long-acting preparations of theophyllinc are used. Such preparations are also useful in the control of nocturnal asthma. These long-acting forms differ, and a patient stabilized on one preparation should not lie transferred to another without good cause. See page 118 and’I'able 6.
thiabendazole An anthelinintic effective against a wide range of intestinal parasites. Also useful in creeping eruption.
Dose: 2.3 iiig/kg daily, up to a maximum of 3 g daily for 2-3 days. Side-effects knore marked in the elderly) are nausea, diarrhoea, rash, yellow vision and
jaundice. Mintezol).
thiamine (vitamin Bj Essential for carbohydrate metabolism, but is used clinically in cases of deficiency, as in beri-beri, or when the diet is restricted. Also of value in the neuritis of pregnancy and alcoholism. Dose: 2-5 nig daily; therapeutic 25- 100 ing daily, in severe deficiency 200-300 nig
doily. severe allergic reactions have followed the i.v. injection of thiamine in high-dose mixed vitamin products such as Pabrinex. Anaphylactic treatment must be immediately available. (Benerva).
thiazides See diuretics and page 150.
thioguanine A cytotoxic agent similar in action and uses to nicrcaptopurine, and used to induce and maintain remission in acute myeloblastic and other leukaernias. Dose: 2 ing/kg, daily. Side-effects are bone marrow depression, nausea and jaundice. Manvis). See page 122 and Table 8.
thiopentone A widely used, short-acting I.V. anaesthetic.
Dose: 100-150 nig initially, repeated at intervals of 10-15 seconds as required. Solutions should be freshly prepared, and great care must be taken to avoid extrava&ttion, a-, the solution is very alkaline and may cause tissue necrosis. Infra-arterial injection is even more dangerous.
(Iniraval Sodium).
a’
thiorid zine A tranquillizing drug related  to chlorpromazine, and used in similar doses for the treatment of schizophrenia and other psychiatric conditions. Unlike most related drugs, it has no antiemetic properties.
Dose: 30-600 ing daily. (Melleril). See page 168 and Table 30.
thiotepa A cytotoxic agent used mainly by infra-cavity instillation, particularly for recurrent superficial tumours of the bladder.
Dose: 15-60 mg dissolved in 60 nil of water, instilled weekly for 4 weeks,
followed by a rest period of 2 weeks before lorther doses are given.
thymoxamine A peripheral vasodilator that is useful in vasospastri and other peripheral ischaemic conditions.
Dose: 160-2,10iiig daily. Side-effects such as headache and facial flushing are usually mild and transient. Treatment should be discontinued after 2 weeks if there is tit) response. (Opilon). See 111oxisylyte.
thyroxine The active constituent of thyroid, but now prepared synthetically. Thyroxine is a powerful metabolic stimulant, specific in neonatal hypothyroidism (cretinism) and myxcredenia. In the former, early diagnosis

halothane A potent non-inflammable inhalation anaesthetic. It suppresses mucous and bronchial secretions, and reduces capillary bleeding. It has sonic muscle-relaxant properties, but in major surgery, supplementary treatment with a muscle relaxant is necessary. Halothane may cause some cardiac irregularities, but an occasional serious side-effect is severe hepatotoxicity, particularly after further exposure to the drug within periods of 441 weeks. Such susceptibility cannot yet be detected, so great care is necessary in any cases of liver dysfunction.
(Fluothane).
hamamelis An extract of witch hazel leaves referred to as harnarnelis or witch hazel water is used as a soothing application for bruises and sprains.
Hartmann’s solution An electrolyte-replacement solution containing sodium lactate, sodium chloride, potassium chloride and calcium chloride.
heparin The natural anticoagulant obtained front lung and liver tissue. It is widely used in deep-vein thrombosis and pulmonary embolism.
Dose: by i.v. injection 5000 units initially, followed by 1000-2000 units hourly by i.v. infusion, or 15000 units by s.c. injection 12-hourly under laboratory control. Prophylactic dose before surgery 5000 units, then 5000 units every 8-12 hours for 7 days. Overdosage call be controlled by the i.v. injection of prolamine sulphate. Treatment with heparin may be combined with that of oral anticoagulants such as phenindione or warfarin to provide immediate action before the slow-acting oral drugs begin to take effect. Occasional side-effects include hypersensitivity reactions and alopecia. Heparin is a complex polysaccharide, but certain fragments of that large molecule retain sonic anticoagulant activity, and are referred to as low molecular weight heparins. They are used mainly in the prophylaxis of venous thrombo-embolism, as they have a longer
action than standard heparin. They are given by once-daily s.c. injection, and laboratory control of the bleeding time is not necessary. The dose varies to some extent with the product used.
hepatitis A & 8 vaccines Inactivated hepatitis virus antigens for the protection of individuals highly exposed to the infections. Dose: see data sheets. (I iaverix A;
kncigix B; II–B–Vax).
theroin See diamorphine.
hetastarch A soluble modified starch that is used as a 6% solution with 0.9% sodium chloride as a plasma volume expander. Dose: 500-1500 nil daily by i.v. infusion, up to a maximum of 20 mltkg daily. It is excreted by the kidneys, and care must be taken to avoid circulatory overload. Not for use in congestive heart failure or renal insufficiency. Side-effects are vomiting, chills, fever and urticaria. (clol-IAES; Hespan).
hexachlorophene A slow-acting antiseptic used for skin sterilization, and present in sonic medicated soaps.
hexamine (methenamine) A formaldehyde derivative of low toxicity, occasionally used as a urinary antiseptic. Dose: 2 g daily. It is usually given as hexamine hippurate to ensure the necessary acidification ol’the urine. (Iliprex).
histamine A compound present in a bound form in all mammalian tissues; its release is probably the ultimate cause of many allergic conditions.
histamine H,-receptor antagonists See antihistamines. See page 110 and Table 2.
histamine Hz -receptor antagonists Drugs that (litter from conventional antihistamines in having a selective blocking action on receptors ill the gastric cells that secrete acid. They are widely used in the treatment of peptic ulcer and other conditions requiring a reduction in gastric acid secretion. See page 162 and Table 27.
homatropine An atropine derivative with a similar but more rapid mydriatic action (15-30 minutes), but a shorter duration of effect of about 24 hours. Eye drops
(1-2%) sometimes with cocaine.

hyaluronidase A ’spreading’ factor used to increase the absorption of large-volume s.c. injections. The injection of 1500 units of hyaluronidase, either into the injection site or mixed with the injection fluid, will promote the absorption of 500-1000 mL of electrolyte solution by s.c. drip infusion. (Hyalase).
hydralazine A vasodilator that is useful in the supplementary treatment of hypertension.
Dose: 50- 100 nig daily, usually with a IlliaUide diuretic or a beta-blocking agent. Also given in hypertensive crisis by slots, i.v. injection in doses of 5-10 mg; over-rapid injection may cause a marked fall in blood pressure. Side-effects are nausea, tachycardia and fluid retention (less likely with low doses), but a lupus erythematOSLIS- like syndromemay occur with extended high-dose therapy. (Apresoline). See page 148 and “Fable 21.
hydrochlorothiazide A thiazide diuretic that brings about it marked increase in the excretion of salts and water, and is of value in congestive heart failure and other oedematous conditions. It is also of value iii    as it reduces peripheral resistance, and potentiates the action of some other antihypertensive drugs.
Dose: 50-111(1 Ing daily initially in
oedenia; maintenance dose 25-50 mg daily or oil alternate days. III hypertension, 25-30 Ing daily according to need.
I lydrochlorolhiazidc, like other thiazid”, Increases the excretion of potassium as well as sodium, and in extended treatment supplementary treatment with potassium chloride or effervescent potassium tablets may be required. Side-effects include nausea, rash, dizziness and photosensitivity. (I lydroSaluric). See page 148
and ‘I able 21.
acute lyniphoblastic leukaemia and some lymphomas. In common with some other corticosteroids, hydrocortisone inhibits organ-transplant rejection and in high doses it is given to control incipient rejection.
Dose: varies considerably according to need: for replacement therapy, 20-30 mg daily: in shock, 100-300 mg or more by slow i.v. injection, repeated as required. Side-effects are numerous and include hypertension, oedema, mental disturbances, re-activation of peptic ulcer, muscle weakness and diabetes. Cushing’s syndrome may occur with high doses.
I I ydrocortisone, unlike cortisone, is active topically, in(] is used as eye drops 0.3% (usually with an antibiotic), ointment and cream (0.50/o and 11M, often with an antibiotic to control any secondary infection.
hydroflumethiazide A thiazide diuretic N,ith the actions, uses and side-effects of bendrofluazide.
Dose: 25- 100 nig daily in (lie morning; 25-50 Ing daily in hypertension.
ff lydrenox). See page 148.
hydrogen peroxide solution It contains 5-7% of H 02
, equivalent to about 20 volumes oJ oxygen. It has antiseptic and deodorizing properties, and is used mainly for cleaning wounds. It is also used as a mouthwash (diluted 1:7), and as ear drops (1:4 in water or 501% alcohol).
thydromorphone A potent opioid analgesic of the morphine type. Dose: in severe pain 1.3-2.6 Ing 4 t,-hourly. Walladone).
hydrotalcite Aluminium magnesium hydroxide carbonate. An antacid used in dyspepsia and related conditions.
Dose: I g as required.
55
hydrocortisone The principal corticosteroid, also known as cortisol, that is secreted by the adrenal cortex. It plays a major role in the metabolism of glucose, protein and calcium, in maintaining the electrolyte balance, and in reducing inflammatory and allergic responses. It is used in all cases of adrenocortical insufficiency, including Addison’s disease and after adrenalectomy. It is also used in anaphylactic shock, asthma, rheumatoid disease and allergic states. It is valuable in
hydroxocobalamin A derivative of eydnu,obdlaniin, and now the preferred form of vitamin B,, as it has a more prolonged action.
Dose: in pernicious anaemia and other vitamin 13, deficiency states, I Ing initially ian. repeated 5 times at intervals of 2-3 days; maintenance dose 1 mg by I’ll’
by )CC- Lion every 3 months. It is also given
prophylactically after total gastrectonly. (Cobalin-H; NCO-Cytalliell). See
page 112.

hydroxyapatite A natural substance with a mineral composition somewhat similar to that of bone. It is used as a source of calcium and phosphorus in osteoporosis and other deficiency states. Tablets of 830 mg are available. (Ossopan).
hypermotility of the gastrointestinal tract, and may be useful in spasmodic dysmenorrhoea.
Dose: 40-80 mg daily; in acute spasm, .10 mg by injection. (Buscopan).
hydroxychloroquine An antimalarial with the actions, uses and side-effects of chloroquine. It is also useful in rheumatoid arthritis in doses of 200-400mg daily, and in lupus erythematosus, but side-effects are numerous, and treatment requires expert supervision. (Plaquenil). See page 165.
hypromellose A cellulose-derivative that dissolves in water to form a viscid, colloidal solution. Such a solution is used as a base for eye drops to extend the action of a dissolved ophthalmic drug; to lubricate contact lenses; and to act as a lubricant in chronic, sore eye conditions.
5-hydroxytryptamine See serotonin.
hydroxurea (hydrocarbamide) A cytotoxic agent sometimes used in chronic myeloid leukaemia.
Dose: 20- 30 mg/kg as a single dose daily or 80 nig/kg every third day. Side-effects are nausea, skin reactions and myelo- suppression. (Hydrea). See page 122 and Table 8.
hydroxyzine A mild tranquillizer with some sedative and antihistaminic properties. It is given in the short-term treatment of anxiety, and in pruritus and dermatoses complicated by emotional tension. Dose: 50-400 mg daily. It has the side-effects of the antihistamines, and is not recommended where some sedation is undesirable. (Atarax; Ucerax). See page 117 and Table 3.
hyoscine (scopolamine) An alkaloid obtained from plants of the belladonna group. It is a powerful hypnotic and is widely used together with papaveretum for premedication before anaesthesia in doses of 300-600 pg by s.c. or i.m. injection. It has some antiemetic properties, and is useful in travel sickness and vertigo. Dose: 300 mg 30 minutes before starting the iourney, followed by up to 3 doses 6-hourly. Scopoderm is a patch of 500 pg. Thc side-effects of mouth dryness and dizziness are those of the anticholinergic drugs generally. It is contraindicated in glaucoma. It is used occasionally in terminal care for bowel colic and excessive respiratory secretions. Dose: 600 pg-2.4 mg daily by s.c. infusion.
hyoscine butylbromide A derivative of hyoscine that differs in lacking any central action. It is given in spasm and
I
ibuprofen A non-steroidal anti-inflammatory agent (NSAID) widely used in rheumatoid and arthritic conditions. It is also given as an analgesic for mild to moderate pain, but not for acute gout. Dose: 1.8 g daily initially; lly; maintenance duos, 600 lllg-L2 daily after food. A 5% cream is available for local use. The sideeflicts are those of the NSAID& generally. (BrUlen; Feribid). See page 165.
ichthammol A thick, dark brown liquid with a characteristic odour, derived from certain bituminous oils. It is a mild antiseptic and is used mainly in chronic eczema as a 100A, ointment or zinc paste. A solution (10% in glycerin) has been used oil ulcers and inflamed areas.
idarubicin A potent cytotoxic agent similar in actions and uses to doxorubicin. It is given orally and i.v. in acute nonlymphocytic leukaemia, breast cancer, and as second-line therapy in acute lymphatic leukaemia. Dose is based on skin area. (Zavedos). See page 122 and Table 8.
idoxuridine An antiviral agent now virtually superseded by acyclovir and related drugs. Used occasionally in herpes zoster skin infection by local application of a 5% solution. See page 144 and Table 19.

fosfamide A derivative of cyclophosphamide with similar actions and uses. It is effective in lung, ovary, breast and soft-tissue tumours, as well as some malignant lymphomas.

Theophylline
Theophylline-type drugs are also known as xanthines or methylxanthines. These drugs are chemically similar to caffeine. They cannot be inhaled, so are taken as tablets or syrup. They start working about 30 minutes after being taken and their effects last for 6-8 hours. Slow-release preparations take 90 minutes to start working, but they last 12-24 hours, and are therefore useful for nocturnal asthma.
In Britain, doctors generally regard theophylline-type drugs as reliever drugs (see p. 152), but rather risky ones whose use is only justified for people with severe asthma. They are given, as an additional treatment, to asthmatics who are not responding well to the usual drug programme (see p. 160). Unfortunately, fairly high doses are needed for theophylline-type drugs to act as relievers, i.e. to reverse bronchospasm. There is a very narrow margin between such a dose and one that causes major (and sometimes dangerous) side effects.
Such side effects usually occur when the doctor is still trying to work out the correct dose – this varies from one person to another, so prescribing theophylline-type drugs is no easy matter. Once you are established on a safe dose (and provided your general health and your intake of alcohol, nicotine and medicinal drugs does not vary – see p. 158) you can usually continue taking theophylline without serious side effects.
In the United States, many doctors also give theophyllinetype drugs, at much lower doses, to people with mild asthma. At these low doses they do not act as relievers, but they have a slight anti-inflammatory effect and therefore act as preventers. The risk of toxicity is much less. Taking low doses of theophylline allows people with mild asthma to reduce their use of beta-2 relievers. However, inhaled steroids are usually more effective in this role, and are the preferred treatment outside the United States.
Side effects
Typical side effects include nausea, vomiting, stomach pains, diarrhoea (sometimes with blood), headache, anxiety, restlessness, insomnia, dizziness, and a pounding heart or irregular heartbeat.
Any side effect of these drugs should be taken seriously and reported to your doctor as soon as possible. If you cannot get an appointment quickly, it may be best to stop taking the drug before seeing the doctor, as long as you have other drugs to control your asthma. Call your doctor for advice.
It is remarkably easy to overdose when taking these drugs at higher doses (see p. 157). Such overdoses can be fatal. The symptoms include repeated vomiting, shaking, feeling unusually hot, needing to urinate frequently, severe thirst, maniacal behaviour, and irregular heartbeat (palpitations). Delirium and convulsions may occur shortly afterwards, so get hospital treatment urgently if you have any of these symptoms.
Unfortunately, a serious overdose can sometimes occur in people who have taken theophylline-type drugs without trouble for many years. There may be no advance warning that anything is wrong - no mild side effects preceding the serious ones. To protect yourself against this, you need regular blood tests from your doctor.
One fundamental problem with theophylline-type drugs is that many different factors - including diet, illnesses other than asthma, and taking other drugs - can alter the way your body deals with the drug. If your liver is breaking down the drug more slowly than usual, the amount in your blood will rapidly increase, and can reach toxic levels.
These are steps that can help prevent an overdose with theophylline-type drugs:
• If you start taking a new drug of any kind, or stop taking a drug (especially the contraceptive pill), or if you change your intake of nicotine or alcohol, ask your doctor - preferably in advance - if your dose of theophylline-type drug needs to be changed.
• A great many drugs interact with theophylline-type drugs, including the new anti - leukotriene drugs. You should always be cautious with any new drug, but take particular care with two antibiotics - ciprofloxacin (brand name Ciproxin) and erythromycin (various brand names) - and with cimetidine (various brand names), used for stomach ulcers and heartburn.
• If you have flu vaccinations, or develop certain illnesses, especially viral infections, heart disease or liver disease, watch for the typical side effects of theophylline-type drugs (see above) and consult your doctor immediately if any occur. These conditions all change the effects of theophylline-type drugs.
• Don’t eat meals that are very high in fats or oils. A lot of fatty food causes too much of the drug to be released at once from the slow-release preparations and increases the risk of side effects. Avoid sudden, major, changes to your diet.
• See your doctor regularly for check-ups. Simply getting older changes your reaction to these drugs: your dose may need to change over the years.
• If you are at all forgetful about tablets, keep a careful record of when you have taken your theophylline-type drugs. Be very careful never to take a second dose by mistake.
• Talk to your doctor if you are not taking a slow-release form of theophylline (see box below for brand names). There are usually fewer side effects from these than from the ordinary forms of the drug.
• Wear a Medic Alert bracelet (see box on p. 95) saying that you are taking theophylline-type drugs. If you have a severe asthma attack and are taken to hospital, it is important that medical staff know this, so that they do not give you more drugs of this type.
While pregnant or breast-feeding, it may be advisable to stop taking theophylline-type drugs: discuss this with your doctor. Although the drugs do not affect most unborn or newborn babies, there are occasional reports of toxicity. Less seriously, theophylline-type drugs go through into breast milk, and may make babies irritable and restless. This problem can be solved by always taking the drug just after a feed - this reduces the amount in the milk.
Theophylline-type drugs might produce behavioural problems and learning difficulties in young children although this is unproven. Research shows that there are no problems for children over six.
Anti-IgE drugs
For asthmatics with strong allergic reactions, who are not doing well on ordinary treatment, the new anti-IgE drugs, such as omalizumab may be very valuable (see p. 149). They are given as a depot injection under the skin.
Some common brand names
Common brand names of theophylline-type drugs include: slow-release preparations — Lasma, Nuelin SA, Phyllocontin Continus, Slo-Phyllin, Theo-Dur, Uniphyllin Continus
ordinary preparations - Aminophylline, Nuelin Ketotifen
Ketotifen (brand name Zaditen) is an antihistamine (see p. 138), although it has other effects in addition to those of ordinary antihistamines. Most significantly, it stabilises mast cells in a similar way to cromoglycate.
One advantage of ketotifen to many people is that it is taken by mouth, in capsule, tablet or syrup form. When it was first introduced, doctors hoped that it would be of particular help in asthma, but it has not lived up to expectations. However, some asthmatics do find it effective. It is worth trying because, it it works, it could permit you to reduce your dose of steroids.
Ketotifen requires up to six weeks to take effect, so continue taking your previous drugs (e.g. steroids) for at least six weeks, or you will risk losing control of your asthma.
Side effects
Minor side effects from ketotifen include nausea, headache, increased appetite and weight gain, drowsiness, dry mouth and slight dizziness. Do not drive until you are sure that ketotifen does not make you drowsy. Alcohol may pack a more powerful punch than usual, so drink very moderately at first. If drowsiness is a problem, take the drug in the late evening. The sleepy feeling may wear off after a few weeks of taking the drug.
There are no serious side effects from ketotifen, except if taken with drugs for diabetes.
Anti-leukotriene drugs
Leukotrienes are among the messenger chemicals that are produced by mast cells during an allergic reaction (see box on p. 12). They help to perpetuate the inflammatory process begun by histamine, and they amplify the reaction by attracting more immune cells into the area.
The anti - leukotriene drugs fall into two distinct groups:
• those that bind to the receptors for leukotrienes, called leu kotriene- receptor antagonists. Currently, there are two drugs in this group, montelukast (brand name Singulair) and zafirlukast (brand name Accolate). A third drug, pranlukast, is in the pipeline and currently going through its safety trials.
• those that block the production of the leukotrienes altogether, called 5-lipoxygenase inhibitors. There is only one drug in this group at present, zileuton (brand names Leutrol, Zyflo); it is not yet available in Britain.
As regards tackling inflammation, the anti - leukotriene drugs work in a completely different way from either steroids or cromoglycate. This makes them useful as an add-on treatment, supplementing the effects of existing anti-allergy drugs.
For asthmatics, anti-leukotriene drugs may be particularly good in combination with antihistamines – whereas antihistamines alone are singularly unsuccessful in asthma (see p. 138). Recent research suggests that taking antihistamines together with antileukotriene drugs is an effective way to control airway inflammation. However, there have been no large-scale trials of this treatment option yet, and it may be a while before it comes into general use.
In the airways of people with asthma, leukotrienes can directly trigger bronchospasm (contraction of the airway muscles) as well as fostering inflammation and increasing mucus production. This multiple action of leukotrienes makes anti-leukotriene drugs very valuable for asthmatics because they act as both relievers (reversing bronchospasm) and preventers (tackling inflammation). They are especially useful for exercise-induced asthma.
All the anti-leukotriene drugs are taken in tablet form. If you are trying an anti - leu kotriene drug for the first time, don’t expect any noticeable effects to occur for about three days. Once you are taking the drug regularly, each dose requires 2-4 hours to have its full effect, but goes on working for 12-24 hours in total.
Although anti - leu kotriene drugs have a reliever effect, they cannot give you immediate relief from bronchospasm. Asthmatics must therefore carry a short-acting beta-2 reliever (see pp. 152-3) as well, in case of an asthma attack.
For those who dislike inhalers, or tend to forget to use them, the fact that these drugs are taken once a day in tablet form makes them an attractive option. However, they are expensive, and at present doctors prescribe them mainly for young children who have difficulty inhaling their usual drugs.
Side effects
The side effects noted in safety trials of these drugs were all minor ones:
• zafirlukast – headache, nausea, diarrhoea, pain
• montelukast – headache, diarrhoea, abdominal pain, cough, and flu-like symptoms
• zileuton – upset stomach
As with all new drugs, you should report any unusual symptoms to your doctor, just in case these represent a rare or longterm side effect of the drug (see p. 137).
Very occasionally montelukast provokes allergic reactions, with symptoms such as itchiness, widespread nettle rash (urticaria) or swelling (angioedema).
Zafirlukast and zileuton can both cause liver damage, but this is rare. Your liver function should be closely monitored by the doctor, by means of regular blood tests, and the drug withdrawn at the first sign of trouble. Montelukast can also affect the liver, but this is extremely rare.
The most worrying development noticed to date is the appearance, in a very few people taking zafirlukast or montelukast, of a disorder called Churg-Strauss Syndrome. The symptoms may include a blotchy purplish rash (due to vasculitis – see lower box on p. 73), a flu-like illness, worsening asthma, and numbness or tingling in the limbs. The heart, lungs and nerves are all affected, because eosinophils (see p. 19) are present in large numbers and cause damaging inflammation.
A study of the cases reported so far suggests that this syndrome may not be due to the anti-leukotriene drugs themselves but to other causes – usually (though not always) a reduction in the dose of steroids. Other patients who are not taking antileukotriene drugs, but are reducing or stopping steroids, may also (again, very rarely) develop Churg-Strauss Syndrome. Doctors now suspect that all these patients were already suffering from an underlying eosinophilic disease, which first showed itself simply as asthma, and was quelled by the steroid treatment prescribed for the asthma. The disease was thoroughly masked as long as the patient was using steroids, but when steroids were withdrawn, the underlying disease flared up, producing a wide range of symptoms. In most cases, reintroducing steroids brings these symptoms under control again.
Putting it all together
What is the ideal combination of all these asthma drugs? That is something your doctor can only work out slowly, because it varies from one individual to another.
The conventional approach to asthma treatment is to start patients on a short-acting beta-2 reliever and then, if the symptoms are not controlled, to add other drugs. This approach is called ’stepping up’. The standard steps, or stages, are as follows:
1. Use a short-acting beta-2 reliever only.
2. Add cromoglycate or low-dose inhaled steroids.
3. Try a higher dose of inhaled steroid or a long-acting beta-2 reliever.
4. Try out each of the following in turn: theophylline, anticholinergic drugs, cromoglycate and higher doses of beta-2 relievers (either inhaled or as tablets/syrup).
5. If there is still no success in controlling symptoms, add regular steroid tablets.
Short courses of steroid tablets may be used at any stage, for the control of sudden, severe, attacks.
Over the last ten years, there has been a change of strategy, and very few people are now kept on Stage 1. Inhaled steroids are now given to most asthmatics, even those with relatively mild asthma. Research from Sweden, where widespread use of
inhaled steroids first became general policy, shows considerable benefits to this approach.
If you have gone beyond Stage 2, ’stepping up’ is usually followed by ’stepping down’. In other words, when the symptoms have been well controlled for 3-6 months, doses of some drugs are reduced, or certain drugs stopped altogether. If the asthma flares up again, the dose is increased or the drug reinstated. If there are no problems, and symptoms remain stable for a month or two, another reduction is tried.
An entirely different approach to asthma management is now being tried with some patients – starting off with moderate to high doses of inhaled steroids (equivalent to Stage 3) and then ’stepping down’. The idea is to get the inflammation under control promptly and fully at the outset. This often seems to be the best strategy.
A few asthmatics don’t get much benefit from steroids. If your dose of steroid needs to be raised repeatedly, or you still need to use your reliever daily in spite of taking steroids, you may have steroid-resistant asthma. There are other drugs that can help, including anti-leukotriene drugs and the more powerful anti-allergy drugs (see p. 149).
Alcohol, caffeine and asthma
Some asthmatics experience bronchodilation (opening up of the airways) when they drink alcohol, while others experience
bronchospasm (tightening of the airways). For those whose airways open up, there is probably no harm in sometimes having a drink to relieve your asthma symptoms, assuming these are fairly mild. Clearly, it would not be a good idea to make a daily habit of this.
If your airways tighten up with alcohol, you will probably be pleased to hear that it may not be the alcohol itself. Alcoholic drinks contain a great variety of other ingredients, either derived from the original ingredients or generated during the fermentation process. Called ‘congeners’, these vary from one type of alcoholic drink to another, and they are often the culprits in asthma. So you may well find that, while one kind of alcoholic drink has a bad effect, another is fine.
Caffeine has a far more uniform effect — for most asthmatics it opens up the airways. However, the amount needed to relieve an asthma attack will also produce unpleasant side effects, such as a pounding heart or shaky hands. There are also long-term problems with such high doses of caffeine, including insomnia, headaches, nervousness and ‘restless legs’. It is much better to use your reliever inhaler to control an attack: the drug in the inhaler has been chemically tailored to give the maximum therapeutic benefit with the minimum of side effects. Anyone who consumes tea or coffee excessively can make themselves seriously ill, either physically or mentally, and it is not always obvious that caffeine is the cause (see p. 235).