Posts Tagged ‘enzyme’

Generic Name
Captopril (KAP-toe-pril)
Brand Name  Capoten
Combination Products
Generic Ingredients: Captopril + Hydrochlorothiazide [M Capozide
Type of Drug
Angiotensin-converting enzyme (ACE) inhibitor.
Prescribed For
High blood pressure and heart failure; diabetic kidney damage and post-heart attack management; also used for kidney hyperten-Sion, the management of people with a high risk of heart disease, chronic kidney disease, the prevention of a second stroke, and high blood pressure associated with other medical conditions, such as scleroderma and Takayasu’s disease.
General Information
Captopril and other ACE inhibitors work by preventing the conversion of a hormone called angiotensin I to another hormone called angiotensin 11, a potent blood-vessel constrictor. Preventing this conversion relaxes blood vessels, helps to reduce blood pressure, and relieves the symptoms of heart failure. Captopril also affects the production of other hormones and enzymes that participate in the regulation of blood-vessel dilation. Captopril usually begins working about 1 hour after it is taken.
In addition to its labeled uses, captopril has been studied in the diagnosis of certain kidney diseases and of primary aldosteronism; in the treatment of rheumatoid arthritis; in swelling and fluid accumulation; in Bartter’s syndrome; in Raynaud’s disease; and in post–heart attack treatment when the function of the left ventricle is affected.
Cautions and Warnings
Do not take captopril if you are allergic or sensitive to any of its ingredients. Severe sensitivity reactions can occur in hemodialysis patients or in those undergoing venom immunization.
People with impaired kidney function should not take captopril unless other anti hypertensives have not worked or have had unacceptable side effects.
Swelling of the face, extremities, or throat has been known to occur with captopril, which can be dangerous (see “Special Information”).
Although not common, captopril may cause very low blood pressure. It may also affect your kidneys, especially if you have congestive heart failure. Your doctor should check your urine for protein content during the first few months of captopril treatment. Captopril may cause a decline in kidney function.
Captopril may affect white-blood-cell counts, possibly increaSlN I)Ur susceptibility to infection. Your doctor should monitor your blood counts periodically.
Captopril can cause serious injury or death to the fetus if taken during pregnancy. Pregnant women should not take captopril.
ACE inhibitors may be less effective in some black patients with high blood pressure, especially when dietary salt intake is high. Nevertheless, they should still be considered useful blood pressure treatments. Swelling beneath the skin to form welts is more common among black patients.
Possible Side Effects
♦    Most common: rash, itching, and cough that usually goes away a few days after you stop taking the drug.
✓    Less common: dizziness, tiredness, sleep disturbances, headache, tingling in hands or feet, chest pain, heart palpitations, feeling unwell, abdominal pain, nausea, vomiting, diarrhea, constipation, appetite loss, dry mouth, breathing difficulties, and hair loss.
♦    Rare: Rare side effects can occur in almost any part of the body. Contact your doctor if you experience any side effect not listed above.
Drug Interactions
•    The blood-pressure-lowering effect of captopril is additive with diuretic drugs and beta blockers. Any other drug that causes a rapid blood-pressure drop should be used with caution if you are taking captopril.
•    Combining 325 mg of aspirin a day with captopril carries a higher risk of death than taking lower doses (less than 160 mg a day). People taking aspirin to prevent a heart attack should use the lower dose.
•    Captopril may increase the effects of lithium; this combination should be used with caution.
•    Mixing any ACE inhibitor with an NSAID pain reliever can increase the chances of kidney failure.
•    Severe sensitivity reactions can occur in those taking allopurinol.
•    Captopril may increase blood-potassium levels, especially when taken with dyazide or other potassium-sparing diuretics.
•    Antacids and captbe taken at least 2 hours apart. 1 tapsaicin may trigger or aggravate the cough associated with captopril.
•    Inclomethacin may reduce the blood-pressure-lowering effect of captopril.
•    Phenothiazine sedatives and antivomiting agents may increase the effects of captopril.
•Probenecid increases captopril’s effect as well as the chance of side effects.
•    The combination of allopurinol and captopril increases the chance of an adverse drug reaction.
•    Captopril may affect blood levels of digoxin. More digoxin in
the blood increases the chance of digoxin-related side ef-
fects, while less digoxin in the blood can compromise its
effectiveness.
Food Interactions
Captopril should be taken 1 hour before a meal.
Usual Dose
Adult: 25 mg 2 or 3 times a day to start. Dosage may be increased to 450 mg a day in divided doses, if needed. Dosage must be tailored to your needs. People with poor kidney function must take lower doses.
Child: 0.14-0.28 mg per lb. of body weight, 3 times a day. Infant: 0.07-0.14 mg per 1b. of body weight.
Overdosage
The principal effect of captopril overdose is a rapid drop in blood pressure, which may lead to dizziness or fainting. Take the overdose victim to a hospital emergency room immediately. ALWAYS bring the prescription bottle or container.
Special Information
Captopril may cause swelling of the face, lips, hands, and feet. This swelling may also affect the larynx (throat) and tongue and interfere with breathing. If this happens, go to a hospital emergency room at once. Call your doctor if you develop a sore throat, mouth sores, abnormal heartbeat, chest pain, a persistent rash, or losses in the sense of taste.
People who are already taking a diuretic (an agent that increases urination) may experience a rapid blood-pressure drop after their first dose of captopril or when their captopril dose k!Z,iTlr_Teased. To prevent this, your doctor may tell ‘you to stop taking your diuretic or to OYtM8 _’ your salt intake 2 or 3 days before starting captopril. The diuretic may then be restarted gradually.
You may get dizzy if you rise to your feet too quickly from a sitting or lying position when taking captopril.
Avoid strenuous exercise or very hot weather because heavy sweating or dehydration may lead to a rapid drop in blood pressure.
Avoid over-the-counter stimulants that can raise blood pressure while taking captopril, including diet pills and decongestants. Also, do not use potassium supplements or salt substitutes containing potassium without consulting your doctor.
If you forget to take a dose of captopril, take it as soon as you remember. If it is within 4 hours of your next dose, take 1 dose immediately and another in 5 or 6 hours, then go back to your regular schedule. Do not take a double dose.
Special Populations
Pregnancy/Breast-feeding: ACE inhibitors can cause fetal injury or death. Women who are or might be pregnant should not take ACE inhibitors. If you become pregnant, stop taking captopril and call your doctor immediately.
Small amounts of captopril pass into breast milk. Nursing mothers who must take this drug should consider using infant formula.
Seniors: Seniors may be more sensitive to the effects of captopril due to age-related declines in kidney or liver function.

Bosentan
Type of Drug     Endothelia receptor antagonist.
Prescribed For
Pulmonary arterial hypertension.
General Information
These drugs lower blood pressure by working on the endothelin system. Endothelia is a hormone that plays an important role in maintaining blood pressure. It is normally found in blood vessels, but endothelin levels are very high in the blood and lungs of people with pulmonary arterial hypertension. People with this condition have high blood pressure, trouble breathing, and get very tired even when walking or doing other moderate exercising. Pulmonary arterial hypertension can be fatal.
Cautions and Warnings
These drugs should not be used by those who are allergic or sensitive to any of their ingredients.
Bosentan can cause liver injury. People taking these drugs should have their liver enzymes checked monthly. Enzyme increases can be a sign of liver injury and may be a reason to stop taking bosentan.
These drugs are broken down in the liver. People with liver damage should take them with caution.
These drugs should not be taken during pregnancy as they are likely to cause birth defects (see “Special Populations”).
These drugs cause a reduction in red blood cells, leading to anemia. Larger doses of bosentan cause a greater loss of red blood cells.
Possible Side Effects
Ambrisentan
Most side effects are mild. Only stuffy nose increases with increased dosage.
V Most common: swelling k%) -aims or legs, stuffy nose, si1)u6fis, flushing, heart palpitations, abdominal pain, constipation, difficulty breathing, and headache.
Bosentan
♦ Most common: headache and sore throat and nose.
Drug Interactions
•    It is possible that bosentan may cause failure of hormonal contraceptives.
•    Cyclosporine, used to prevent transplant rejection, increases blood levels of bosentan and ambrisentan. Do not combine these drugs.
•    Mixing glyburide, an antidiabetes drug, with bosentan increases the risk of elevated liver enzyme levels. Do not combine these drugs.
•    Ketoconazole greatly increases blood levels of bosentan by slowing its breakdown in the liver.
•    Combining bosentan with a statin-type cholesterol - lowering drug such as simvastatin, lovastatin, or atorvastatin reduces the amount of statin drug in the blood. Dose increases may be needed.
•    Bosentan can reduce the amount of warfarin in the blood by
about 1/3. Changes in warfarin dosage may be needed.
•    Combining ambrisentan with atanazavir, clarithromycin, indinavir, itraconazole, ketoconazole, nelfinavir, ritonavir, omeprazole, saquinavir,or telithromycin may increase the amount of ambrisentan in the blood. Caution is advised.
•    Combining ambrisentan with rifampin may reduce the
amount of ambrisentan in the blood. Caution is advised.
Food Interactions
These drugs may be taken with or without food.
U’Suk Dose
Ambrisentan
Adult (age 18 and over): 5-10 mg once a day. Do not crush, split, or chew these tablets.
Child: not recommended.
Possible Side Effects (continued)
♦    Common: flushing, abnormal liver blood pressure, and heart
♦    Less common: upset stomach, tiredness.
ver function, leg swelling, palpitations.
, swelling, itching, anemia,
Bosentan
Adult (age 18 and over): 62.5 mg twice a day for 4 weeks, then
125 mg twice a day.
Child: not recommended.
Overdosage
Massive overdose may result in severe lowering of blood pressure, requiring emergency attention. The most common effects associated with overdosage are headache, low blood pressure, increased heart rate, and nausea and vomiting. Overdose victims should be taken to a hospital emergency room for treatment. ALWAYS bring the prescription bottle or container.
Special Information
Do not stop taking these drugs without gradually reducing the dosage as instructed by your doctor.
If you forget to take a dose, 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.
Contact your doctor at once if you develop severe itching, yellowing of the skin or eyes, tiredness, swelling in the arms or legs, nausea, vomiting, fever, or abdominal pain.
Doctors must enroll in special restricted distribution programs before they can prescribe these medicines, because of the risks of liver injury and birth defects associated with them. These medicines are not available in regular pharmacies but are mailed to you from a central pharmacy only after the testing and other program requirements have been met by your doctor.
Special Populations
Pregnancy/Breast-feeding: These medicines are very likely to cause major birth defects and should not be taken by pregnant women. Women must be sure they are not pregnant before beginning these treatments.
Women should also use non-hormone contraceptives while on these drugs. Hormone-based contraceptives such as birth control pills, injections, and implants may not work in women taking Wst m or ambrisentan.
It is not known if either of these medicines passes into breast milk. Nursing mothers should use infant formula.
Seniors: The greater chance of kidney, liver, and cardiac function side effects in seniors may affect drug dosage. Seniors may also experience more swelling in the arms or legs.

abciximab A monoclonal antibody that inhibits platelet aggregation and thrombus formation. Used as an adjunct to heparin in percutaneous transluminal coronary angioplasty under expert supervision. (ReoPro).
glaucoma, as it decreases intraocular pres    9 sure by reducing formation of aqueous humour. It has also been used in epilepsy. Dose: 250 nig-1 g daily. In severe conditions it may be given in similar doses by i.v. injection. Side-effects are drowsiness, gastrointestinal disturbances and paraesthesia. (Dianiox). See page 138 and Table 16.
acamprosate An analogue of GAGA used in alcoholism. It assists in the maintenance of abstinence in alcohol-dependence, but prolonged treatment for a year may be required. Dose: 666 mg 3 times a day. (Campral).
acarbose An inhibitor of alpha-glucosidase, the enzyme that converts dietary carbohydrates to soluble sugars. Used in noninsulin-dependent-diabetes to reduce hyperglycaemic peaks after food. Dose: 50 mg daily initially, rising to 150 mg daily if required. Side-effects are flatulence and diarrhoea; a hypoglycaemic reaction can be treated with oral glucose. (Glucobay). See page 131 and Table 13.
ACE inhibitors See angiotensin-converting enzyme inhibitors.
acebutolol A beta-adrenergic blocking agent with the actions, uses and side-effects of propranolol, but with a more cardioselective effect and less likely to cause bronchospasm.
Dose: in hypertension, 400-800 mg daily; in severe angina, up to 1.2 g daily. It is contraindicated in cardiogenic shock, atrioventricular-block and heart failure. Care is necessary in obstructive airway disease and renal failure (Sectral). See page 148 and Table 21.
aceclofenec A non-steroidal anti-inflammatorydrug (NSAID) used for the relief of pain in arthritic and rheumatoid conditions. Dose: 200 mg daily. (Preservex). See page 131 and Table 29.
acemetacin A derivative of indomethacin with similar actions and uses, but said to be better tolerated.
Dose: 120-180 ing daily. (Finflex). See page 165 and ‘[’able 29.
acetazolamide An inhibitor of the enzyme carbonic anhydrase that has been given as a mild diuretic, as it increases the excretion of bicarbonate. Now used mainly in mild
acetomenaphthone A synthetic form of vitamin K, formerly used in prothrombin deficiency. Menadiol and phytonienadione are now preferred. Acetoinenaphtlione is present in some chilblain preparations.
acetylcholine The neurotransmitter of the parasympathetic nervous system. A 1% solution is sometimes used as a miotic to obtain rapid contraction of the pupil after cataract surgery. (Miochol).
acetylcysteine A mucolytic agent used as eye drops 5% in tear deficiency. Of value in the early treatment (10-15 hours) ofparacetarnol poisoning.
Dose: initially 150 nig/kg by slow i.v. injection, followed by smaller doses up to a total dose of 300 mg/kg over 20 hours. It is inef1ictive, and possibly harmful, if given at a later stage. (Parvolex). See methionine.
acetylsalicylic acid See aspirin. aciclovir See acyclovir.
acipimox A derivative of nicotinic acid used in hypercholesterolaemia.
Dose: 500–750 mg daily. Side-effects are hushing, erythema, nausea and malaise. (Olbetani). See page 146 and Table 20.
acitretin A vitamin A derivative (retinol) used in severe psoriasis resistant to other treatment.
Dose: 20-30 mg daily. Teratogenic - see specialist literature. (Neotigason).
aclarubicin An anthracene cytotoxic agent of the doxorubicin type used in resistant acute non-lymphatic leukaemia. (Aclacin). See specialist literature.
acrivastine one of the newer antihistamines. It is less likely to cause drowsiness, as it does not cross the blood-brain barrier to any great extent, but is correspondingly less effective in non-allergic pruritus. Dose: 24 mg daily. (Semprex). See
page 110 and Table 2.

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.

sodium picosulphate A synthetic laxative similar to bisacodyl, but with a slower action.
Dose: 5-15 rug at night.
sodium stibogluconate An organic antimony drug use([ in the treatment of visceral leishmaniasis or kala-azar.
Dose: 20 ruglkg daily by i.m. or i.v. injection for 30 days. Side-effects include anorexia, vomiting, cough and sub-sternal pain. (Pentostain).
I sta
given by i.v. injection as a 50% solution to promote diuresis and to reduce cerebral oedema.
sotalol A beta-adrenergic blocking agent used ill the treatment of hypertension, angina, cardiac arrhythmias and thyrotoxicosis. Dose: 120 nig initially, increased as required; maintenance, 160-600 ing daily. For prophylaxis after infarction, 320 mg daily. In acute cardiac arrhythmias, 20-60 mg by slow i.v. injection under ECG control. Care is necessary in heart block, asthma, hepatic and renal impairment. (BetaCardone; Sotacor). See pages 114 & 148, and Tables 4 & 2 1.
sodium tetradecyl sulphate A venous-occluding agent used in the injection sclerotherapy of varicose veins.
Dose: 0.5-1 nil at any one site, followed by compression bandaging for sonic weeks. The local irritant action of the drug brings about an occlusive venous fibrosis at the injection site. Extra-vascular injection may cause necrosis. Care is necessary in allergic subjects.
sodium thisulphate A 50% solution is given by i.v. injection in cyanide poisoning. See sodium nitrite and kelocyanor.
sodium valproate An anticonvulsant
effective in most forms of epilepsy.
Dose: 600 mg daily in adults initially, increased if required up to a maximum of 2.5 g daily. It may also be given by slow i.v. injection in doses of,100-800ing, followed by similar doses given by i.v. infusion. Liver function tests before and during treatment are essential. Severe side-effects such as vomiting, drowsiness or jaundice require withdrawal of the drug, as does spontaneous bleeding or bruising.
(Epilim). See page 136 and Table 15.
somatropin A form of human growth hormone obtained by biosynthesis. It is used to stimulate growth in hormone-deficient young patients whilst the epiphyses are still open.
Dose: 0.07 units/kg daily by i.m. or s.c. injection. Subcutaneous injection sites should be varied. (Genotropin; Hurrialrope; Norditropin; Salzen).
spectinomycin An antibiotic used in the treatment of penicillin-resistant gonorrhoea.
Dose: 2-4g by deep Lin. injection. Side-effects include nausea, dizziness and tirlicaria. (Trobicin).
spironolactone An aldosterone antagonist which potentiates the action of thiazide and loop diuretics in sonic resistant conditions. It is of value in the oedema of liver cirrhosis, as well as in the nephrotic syndrome and congestive heart failure. Dose: 100 ing daily up to a maximum dose of 400 mg daily. Side-effects include drowsiness, gastrointestinal disturbances, gynacconiastia and an increased sensitivity to warfarin. The combined use of potassium-sparing diuretics or potassium supplements is contraindicated.
(Aldacione; Spiroctan).
SSRls See selective serotonin re-uptake inhibitors.
stanozolol An anabolic steroid with actions and uses similar to those of nandrolone. Dose: 5 ing daily. It also has fibrinolytic properties, and is used in lipoderinatosclerosis (a complication of deep-vein sclerosis), and in some forms of vasculitis. It may also be of sonic value in hereditary angioneurotic oedema and in the relief of itching due to biliary obstruction. Also used in some aplastic anaemias, 2.5-10 ing daily. Sonic androgenic side-effects may Occur, bill are usually mild and reversible Oil stopping treatment. (Stroniba).
93
sorbitol A saccharide that after absorption is converted in the liver almost entirely to laevulose. It has been used as a sugar-substitute in diabetes, and it is sometimes
starch Carbohydrate granules obtained from maize, rice, wheat or potato. Widely used as absorbent dusting powder.

stavudineV An antiviral agent that inhibits the enzyme reverse transcriptase, and so indirectly blocks the synthesis of viral DNA. It is used in HIV infections resistant to or not responding to zidovudine. Dose: 00 ing daily, I hour before food. Side-effects include malaise, peripheral neuropathy and pancreatitis. (Zerit). See page 144 and *['able 19.
sterculia A natural gum that swells in water to a gelatinous mass. It is used as a bulk laxative as when taken with plenty of water it increases faecal volume and promotes peristalsis. It is also used in diverticulitis and irritable bowel syndrome, and as an appetite suppressant. Dose: 5-10g daily but not at night. (Normacol).
Sul
Dose-. I g daily by deep i.m. injection. Its use requires care. as it k both ntotnxir and nephro(oxic, especially in full doses and in renal impairment. Measurement of the plasma concentration QfbErCplU1llV0ll P. advisable during treatment. Cutaneous sensitization has followed contact of the drug trill the skin.
sucralfate An aluminium sucrose sulphate use,] in the treatment ofpeptic ulcer. It is not an antacid, but forms a barrier over the ulcer that is resistant to peptic attack and so promotes healing.
Dose: 4g daily for at least 4 weeks. Antacids should not be taken immediately before or after sucralfate. (Antepsin). See page 162.
94
stilboestrol A synthetic oestrogen with the actions and uses of oestradiol.
Dose: 0.1-0.5 mg daily for menopausal symptoms, but it is now prescribed less frequently. Dose in breast cancer, 10-20 mg daily; in prostatic carcinoma, 3 mg daily or more, although fosfestrol is often preferred. Side-effects include nausea, fluid retention, thrombosis, impotence and gynacconlastia.
streptokinase Ali enzyme preparation obtained from cultures of haemolytic streptococci. It has fibrinolytic properties, and is of value in deep vein thrombosis, pulmonary embolism, myocardial infarction and other conditions requiring fibrinolytic therapy.
Dose: by i.v. infusion, 250000 units or more initially, followed by maintenance doses of 100000 units hourly for up to 72 hours. For myocardial infarction
1 5(10000 units over l hour. Side-effects are fever, rash, haemorrhage and allergic reactions. (Kabikinaw; Streptase).
sulconazole A synthetic antifungal agent similar in actions and uses to miconazole. Applied as a 1% cream twice daily. (Exelderin).
sulfadoxine A long-acting sulphonamide, with the general antibacterial action of the group. It has been used in the treatment of leprosy.
Dose: I-1.3f; weekly. In association with pyrimethainine, it is used in the treatment of malaria, but the use of such mixed products requires great care, as severe, sometimes fatal side-effects have occurred. It is no longer used for malaria prophylaxis. (Fansidar).
sulfametopyrazine A very long-acting sulphonamide used mainly in chronic bronchitis and urinary tract infections. Dose: 2 g once it week. Side-effects and toxic reactions, although mainly those of the sulphonamides generally, may be linked with the slow excretion of the drug. (Kelfizine).
streptokinase- streptodornase A mixture of enzymes obtained from cultures of haemolytic streptococci. It brings about the dissolution of blood clots and the liquefaction of purulent exudates, anti is used as a solution to clean foul wounds, pressure sores and ulcers. (Varidase).
streptomycin The first of the amino-glycoside antibiotics, but now used mainly as part of the multi-drug treatment of tuberculosis.
sulindaC A non-steroidal anti-inflammatory analgesic agent (NSAID) with actions, uses and side-effects similar to naproxen. It is of value in the pain and inflammation of rheumatoid disease and acute gout. Dose: 200-400 ing daily with food. It may cause gastrointestinal disturbance and occasional bleeding. (Clinoril). See
page 165 and Table 29.
sulphadiazine one of the more active and less toxic sulphonamides. It is used mainly in the treatment of severe conditions such as meningococcal meningitis.

Dose: (, 9 g daily by deep i.m. injection or i.v. infusion for 2 days, followed by 2 g or more orally daily. Dose in the prevention of rheumatic fever I g daily. Side-
effects are nausea, rash and blood dyscrasias.
sulphadimidine One of the least toxic of the sulphonamides, now used mainly in urinary infections.
Dose: 2 g initially, with maintenance of 1. - 4 g daily orally. Side-effects include nausea, drug fever, rash and leucopenia.
sulphamethoxazole A sulphonamide present with trimethaprim in co-trinioxazole.
sulphasalazine A sulphonamide derivative that is taken up selectively by the connective tissues of the intestines. It is used in the treatment and maintenance of remission in ulcerative colitis and Crohn’s disease.
Dose: 4-8g daily initially; maintenance, 1.5-2 g daily. 11 is also given as a 3 g enema and as 500 mg suppositories. Occasionally given in rheumatoid arthritis in doses of 03-3 g daily. Side-effects include nausea, rash, drug fever and blood dyscrasia. If blood dyscrasia is suspected, a blood count should be done and the drug withdrawn. (Salazopyrin). See niesalazine, olsalazine, page 172 and’I'able 32.
sulphathiazole One of the early sulphonamides, and survives in a few mixed products.
sulphinpyrazone. A uricosuric agent with the selective action of increasing the excretion of uric acid, hence used in the treatment of chronic gout and hyperuricaemia. Dose: 100-200 mginitially with food, increased according to the plasma uric acid levels up to 60(1-800 nag daily, with tower maintenance doses according to need and response. Side-effects are nausea, abdominal pain and rash. Care is necessary in peptic ulcer and renal impairment, and blood counts are necessary during, treatment. Salicylates antagonize the action of the drug. (Anturan). See
page 1.10 and Table 17.
sulphonamides A group of drugs that have an antibacterial action by preventing the uptake and use of folic acid. They are thus bacteriostatic and not bactericidal in action. The use of the sulphonamides ides has
declined, and they are now used mainly in urinary tract infections due to sulphonamide-sensitive bacteria. The side-effects of the sulphonamides include nausea, dyspepsia, diarrhoea and allergic reactions. Bone marrow depression may occur if treatment is prolonged. The uncommon Stevens-Johnson syndrome is a very serious reaction. See sulphadiazine ind co-trinioxazole.
sulphonylureas A group of orally active drugs represented by chlorpropamide that promote the release of insulin from the beta-cells of the pancreas. They are used in mild diabetes not controlled by diet, and in the late-onset diabetes of middle age, but they are not suitable for the treatment of juvenile diabetes. The presence of some still-functioning beta-cells is essential for sulphonylurea activity. Side-effects include weight gain, rash, fever and jaundice. During illness and pregnancy, insulin treatment should replace sulphonylurea therapy. See page 131 and Table 13.
sulphide An antipsychotic drug with a central action on dopaminereceptors. It is used in the treatment of acute and chronic schizophrenia, as in low doses it increases awareness in apathetic and withdrawn patients, and in larger doses controls the active forms of the illness.
Dose: 400-800 mg daily: in severe conditions up to 2.4 g daily. The side-effects are similar to those of chlorpromazine. (Dolmatil; Sulparex; Sulpitil). See
page 168 and Table 30.
sumatriptan A serotonin agonist used in
i lie treatment of acute migraine. (It is not suitable for prophylaxis.)
Dose: 50-100 mg orally as soon as possible after onset of an attack, but a second dose should not be given for the same attack, but may be repeated once if migraine symptoms recur. In severe migraine an(] cluster headache 6 mg by S.C. injection, but not more than 12 nig in 24 hours. (Pre-filled syringes and an auto-injector are available.) If should not be given until 24 hours after other antimigraine treatment, or any other drug that influences the re-uptake of serotonin. Side-effects include tingling and tightness in any part of the body, and an angina-like chest pain that may be severe. (I migran). See page 154 and Table 23.

nisoldipine A calcium channel blocking agent of the nifedipine type. Used in mild to moderate hypertension pertension and in the prophylaxis of chronic angina.
Dose: 10 ing once daily before breakfast with adequate fluid, slowly increased as required up to 40 mg daily. Tablets to be swallowed whole, not chewed or crushed. It may react with sonic other drugs in common use, and grapefruit juice should be avoided. (Syscor). See pages 114 & 148, and ‘Fables 4 & 21.
nitrazepam A benzodiazepine used as a mild hypnotic when some degree of daytime sedation is acceptable.
Dose: 5-10 mg at night, with reduced doses for elderly patients, and in renal and’ hepatic dysfunction. Care is necessary in respiratory depression. Some dependence on nitrazepam may occur, so extended treatment should be avoided. The combined use of alcohol increases the hypnotic action. (Mogadon; Remnos). Set: page 152 and Table 22.
Nitrocine A solution of glyceryl trinitrate, for i.v. infusion in myocardial ischaemia and refractory angina.
nitrofurantoin An antibacterial agent with a wide range of activity against the majority of urinary pathogens. It is of value in cystitis and pyelitis, and in renal infections that have become resistant to other drugs. It is also used prophylactically but extended use requires care.
Dose: 400 mg daily; 50-100 mg at night for prophylaxis. It is ineffective in an alkaline urine. Nausea, rash and peripheral neuropathy are side-effects, and acute and chronic pulmonary reactions have been reported. (Furadantin; Macrobid).
nitroglycerine See glyceryl trinitrate. nitroprusside See sodium nitroprusside.
nitrous oxide The oldest inhalation anaesthetic. Supplied in blue cylinders, it is widely used for induction and as part of a mixed anaesthetic system. It is also used as
a 50% oxygen mixture as an inhalation analgesic in obstetrics.
nizatidine A potent and selective H,-receptor antagonist chemically distinct from cimetidine or ranitidine.
Dose: in the treatment of benign duodenal and gastric ulcer, single doses of 300 mg daily, taken in the evening, or 150 mg twice a day, and continued for 4 weeks, or for s weeks in gastric ulcer including non-steroidal anti-inflammatory agent (NSAID) -induced ulceration. Occasionally given by i.v. infusion in doses of300mg daily. For prophylactic maintenance, doses of 150 mg daily may be given for up to a year. Reduced doses should be given in renal impairment. Side-effects include headache, niyalgia, cough, pruritus and abnormal dreams. (Axi& Zinga). See page 162 and “Fable 27.
non-steroidal anti-inflammatory drugs (NSAIDs) A group of drugs with analgesic anti-inflammatory properties widely used in arthritic, rheumatoid and related conditions. The response to a NSAID and the incidence and severity of side-effects such as gastric irritation and renal toxicity vary considerably, and the best NSAID for an individual patient is the one that gives optimum relief with minimal side-effects. The NSAIDs, of which aspirin is the oldest example, act by interrupting the biosynthesis of prostaglandins from arachidonic acid, in which process the enzyme cycleoxygenase (COX) plays a key role. It is now known that COX exists in two forms identified as COX-1 and COX-2. The anti-inflammatory action of the NSAIDs appears to be linked with the inhibition of COX-2, whereas the unwanted side-effects are associated with COX- I inhibition. Different NSAIDs have varying degrees of activity against the different forms of COX, which may explain the differences in the therapeutic response and the incidence of side-effects. Recently, a NSAID (meloxicain) has been introduced that has a more selective inhibitory action on COX-2, with which the incidence of side-effects appears to be lower than with the older drugs, and so may have therapeutic advantages. In general, the response to a NSAID may take 1-3 weeks to develop fully, but monitoring for gastrointestinal bleeding may be advisable if treatment is extended. A NSAID should not be given to a patient with a history of asthma or hypersensitivity, nor when peptic ulcer is suspected or present. In all cases, treatment should be commenced with the lowest recommended dose, and caution is necessary in the elderly, and when renal or hepatic function is impaired. See page 165 and Table 29.
Dose: 20 100 mg daily. It is given in nocturnal enuresis in doses of 10-20 mg nightly, but the duration of treatment should not exceed 3 months. (Allcgron). See page 128 and Table 11.
76
noradrenaline (norepinephrine) The pressor hormone released at sympathetic nerve endings when such nerves are stimulated. It is also present with adrenaline in the medulla of the adrenal gland. It raises blood pressure mainly by a general vasoconstriction, whereas adrenaline acts by constricting the peripheral vessels and increasing the cardiac output. Noradrenaline is given by slow i.v. infusion in the treatment of shock, peripheral failure, and low blood pressure states, but the response may fluctuate with small variations in dose. The value of vasoconstrictors in shock is now questioned, as in shock the peripheral resistance may well be high, and the blood supply to essential organs such as the kidneys may be reduced.
Dose: 2-20 pg/niin, based on need and response. Great care must be taken to avoid extra-venous injection. (Levophed).
norethisterone An orally active progestogen. Used in amenorrhoea, functional uterine bleeding and dysmenorrhoea. Dose: 5-20 mg daily. In breast cancer, large doses up to 60 mg daily have been used. To postpone menstruation, 15 mg daily for 3 days have been used. In small doses, and in association with an oestrogen, norethisterone and related drugs are widely used as oral contraceptives. See page 264.
norfloxacin A quinolone antibacterial with the actions, uses and side-effects of cinoxacin and other quinolones.
Dose: in acute urinary tract infections, 801) mg daily for 3-10 days: in chronic infections continued for up to 12 weeks. ( I Itinor).
norgestrel (levonorgestrel) An orally active progesterone-like drug and inhibitor of ovulation. Used as a constituent of mixed oral contraceptive products, and as a ‘progestogen -only’ oral contraceptive. See page 264.
nortriptyline A tricyclic antidepressant with actions, uses and side-effects similar to those of amitriptyline, but with a reduced sedative activity.
NSAIDs See non-steroidal anti-inflamma-
tory drugs, page 168 and Table 29.
nystatin A fungicidal antibiotic, used in the treatment of intestinal, vaginal and superficial candidiasis. Oral tablets contain 500 000 units, pessaries contain 100 000 units; cream and ointment 1%. Dose: (oral) 2 million units daily. It is also used as pastilles of 100000 units for mouth infections.
octreotide A synthetic compound that inhibits the release of the growth hormone. It is used in acromegaly, which is caused by an overproduction of the growth hormone by a pituitary tumour and it is given in doses of 100-200pg 8-hourly by s.c. injection. It is also used in the symptomatic treatment of the carcinoid syndrome, in which the release of vasoactive substances by a gastro- pancreatic tumour causes flushing and severe diarrhoea.
Dose: 30 pg by s.c. injection, increased as needed up to 600 pg daily. It has no action on the cause of the syndrome. It is used occasionally in terminal care to reduce intestinal secretions and vomiting. Dose: 300-600 pg by s.c. infusion. (Sandostatin).
oestradloIlThe oestrogenic hormone controlling ovulation and menstruation. It has been used to control menopausal symptoms in doses of 10-20pg daily, but skin patches are now preferred for hormone replacement therapy (HRT). It is used occasionally as s.c. implants for long-term treatment. Oestradiol is also present in some cream preparations for menopausal atrophic vaginitis.
oestriol A natural oestrogen used in intravaginal cream to relieve the atrophic vaginitis and kraurosis vulvae associated with the menopause. Also given in doses of 1-32 mg daily for the genito-urinary symptoms linked with infections in oestrogen deficiency states. (Ovestin).

ofloxacin A fluorinated quinolone with the actions, uses and side-effects of other quinolones such as ciprofloxacin and norfloxacin. It is used mainly in urinary and lower respiratory tract infections. Dose: wii nig daily as a single morning dose. Dose in severe infections 200-400 mg daily by i.v. injection. An occasional side-effect is tendon damage with pain and inflammation, which requires immediate withdrawal of the drug. Exposure to strong sunlight should be avoided. (Tarivid). Also used as eye drops (0.3%) for superficial eye infections. (Exocin).
olanzapineV An antipsychotic agent for the treatment of schizophrenia. It has a more selective action on certain 5-H’I'- receptors, and is less likely to cause extra-pyramidal side-effects.
Dose: 10 mg as a single daily dose, slowly increased as required. Maintenance dose 5-20 mg daily. Side-effects include
sedation and weight gain. (Zyprexa). See page 168 and Table 30.
olsalazine A compound formed from mesalazine, and used in the treatment of ulcerative colitis. It is more slowly
absorbed, and reaches the colon largely unchanged, where it is broken down by intestinal bacteria to release the active metabolite mesalazine.
Dose: 1-3 g daily in acute mild ulcerative colitis; I g daily for maintenance, often for long periods. The common side-effect is a watery diarrhoea. Salicylate sensitivity is a contraindication. Patients are now advised to report any bruising, bleeding or
malaise. I( a blood dyscrasia is suspected, a blood count should be made -,in(] the drug withdrawn. (Dipentuni). See page 172 and Table 32.
ondansetron A potent antiemetic, of value in the nausea and vomiting associated with cancer chemotherapy. Such vomiting appears to be induced by the release of serotonin, which acts on receptors in the gut as well as stimulating the chernoreceptor trigger zone in the brain. Ondansetron is a specific (5—HT,) serotonin blocking agent, and is given before the commencement of cytotoxic treatment or radiotherapy.
Dose: 24 mg daily; in severe vomiting an initial dose of 8 ing is given by slow i.v. injection, followed by I ing/hrly for 24 hours by continuous i.v. infusion, followed by oral therapy. Side-effects are an initial sense of warmth, headache an(] constipation. (Zofran). See page 158.
topium The dried juice from the capsules of the opium poppy. See morphine.
orciprenaline A synipathomimetic agent with the bronchodilator properties of isoprenaline. It is used for the relief of obstructive airway conditions, although more selective drugs of the salbutarnol type are often preferred.
Dose: up to 80 ang daily; by aerosol inhalation up to 12 puffs (9mg) daily. Side-effects include tremor and tachycardia. (Ahiperil). See page 118 and Table 6.
orphenadrine A spasmolytic drug, used in the treatment of parkinsonism, and for the relief of voluntary muscle spasm. Dose: 150-400 nig daily. It may also be given by i.m. injection in doses of 60 mg. In parkinsonism it tends to control the rigidity more than the tremor. Side-effects are anticholinergic and include dryness of the mouth, dizziness and visual disturbances. Weight gain has occurred with high doses. (Disipal; Norflex). See
page 160 and Table 26.
77
omeprazole An inhibitor of the enzyme I I*K’A'I’Pase.’rhat enzyme controls the final stage of gastric acid production, and its inhibition by omeprazole is of value in peptic ulcer resistant to H, receptor antagonists, and in reflux oesophagitis, where such agents are not always effective. Dose: in benign gastric and duodenal ulcer, 20-40 ing as it single daily dose for 4-8 weeks. Larger doses may be required in the Zollinger—Ellison syndrome. Side-effects such as nausea, gasiro-intestinal disturbances and headaches are usually mild. (Losec). See page 162 and Table 27.
oxazepam A benzodiazepine with the actions, uses and side-effects of diazepam. It is useful in acute anxiety and panic states.
Dose: 45-120 mg daily. See page 117 and Table 5.
oxerutins A mixture of rutosides (flavonoid derivatives) which is claimed to reduce capillary fragility and permeability. It has been used in venous disorders of the lower limbs.
Dose: 750-1000 nig daily. (Paroven).

itraconazole An orally active antifungal agent used in the treatment of vulvovaginal candidiasis, pityriasis and tinea infections. Dose: 200 mg twice a day for the I -day treatment of vulvovaginal infections; 200 nig daily for 7 days in pityriasis, 100nig daily for 15-30 days in tinea infections. Side-effects are nausea and abdominal pain. Liver disease is a contraindication. Combined treatment with astiniazole or ierfenadine should be avoided. (Sporonox).
ivermeclin A fungal derivative effective against the microfilaria causing ‘river blindness. It does not kill either the adult worms or their larvae, but prevents the growth of the latter, and treatment must be continued until the adult worms die out. Dose: 150. (Mectizan).
kanamycin An aminoglycoside antibiotic now used mainly in gentamicin-resistant infections.
Dose: I g daily by i.m. injection; 15-30 rng/ kg daily by i.v. infusion. (Kannasyn).
kaolin Aluminium silicate. Used as an absorbent in diarrhoea, colitis, food poisoning, etc., often as Kaolin and Morphine Mixture.
Dose: 10-20 nil as required. It is also used externally as Kaolin Poultice to relieve the pain of sprains, etc.
kelocyanor A specific antidote for cyanide poisoning. See dicobalt edetate.
ketamine A short-acting i.v. anaesthetic with analgesic properties.
Dose: 1-2 mg/kg i.v. over I minute, repeated as required; 4-10 nig/kg by deep Lin. injection. It is used mainly in paediatric anaesthesia, and its analgesic action is also of value in neurodiagnostic procedures, and other painful investigations. Hallucinations may occur during the recovery period. (Ketalar).
ketoconazole A broad-spectrum, orally active antifungal agent. It is of value in systemic and deep mycoses, and in severe and resistant mycoses of the gastrointestinal tract and the vagina. It is also effective in severe mycoses of the skin, but it should be used only for superficial fungal infections not responding to other treatment.
Dose: 200 mg daily with ft)od, up to a maximum of 4tH) mg daily. Side-effects include nausea, rash and pruritus. It may cause hepatitis; liver function tests may be necessary if given for more than 14 (lays. (Ki-zoral).
ketoprofen A non-steroidal anti-inflammatory and analgesic agent of the ibuprofen type. It is of value in rheumatoid arthritis, gout, spondylitis and related conditions, and in dysmenorrhoea.
Dose: 100-200 mg daily with food;
100 Ing by suppository at night, 50-100 mg by deep Lin. injection 4-hourly. Care is necessary in peptic ulcer and hepatic disease. May increase the action of anticoagulants and other drugs bound to plasma protein. (AlrheLiniat; OrUdis; Orivail). See page 165 and Table 29.
ketorolacV A potent analgesic used for the short-term reliefofacute postoperative pain.
Dose: tO mg 4-6-hourly up to 40 ing daily for not more than 7 days; dose by deep i.m. or slow i.v. injection. 10 mg initially, then 30 mg 4-6-hourly up to 90 mg daily for not more than 2 days. Side-effects are numerous; see data sheet. (Toradol). Also used as eye drops (0.51)/0 to reduce pain and inflammation after ocular surgery. (Acular).
keftotifen An antihistamine that may also have some of the properties ofsodium cromoglycate. It is used in the prophylactic treatment of asthma.
Dose: 4 mg daily with food, continued lor ,sine weeks. Other anti-asthmatic therapy should be continued for at least 2 weeks to ensure maintenance of control. Side-
effects include sedation and dryness of the mouth. (Zadi(en). See page 110 and Table 2.
Kogenate A recombinant form of the human blood Factor Vill, given i.v, as replacement therapy in the treatment of haemophilia A.

labetalol A beta - adrenocepior blocking agent with some alpha-blocking activity. Like related drugs, labetalol is indicated in all types of hypertension, including that following myocardial infarction.
Dose: 200 mg daily initially, with food, slowly increased up to a maximum of 2.4 g daily; by i.v. injection 50 mg repeated as required; for the rapid control of the hypertension of pregnancy 20-160 ing by i.v. infusion hourly. It should be used with care in asthma and heart block. Side-effects include weakness, nausea, bradycardia and postural hypotension. Liver damage has been reported. (Trandate). See page 148 and `fable 21.
lacidipine A calcium channel blocking agent with the actions and uses of nifedipine. In hypertension it is given as a single morning dose of 2 nig with food, increased up to 6 mg as the response develops over 3-4 weeks. Half doses in hepatic impairment and the elderly. Early chest pain is an indication that the drug should be withdrawn. (Motens). See page 148 and Table 21.
lactilol A semi-synthetic sugar that is not absorbed orally, and acts as an osmotic laxative by retaining water in the intestinal tract. Also inhibits ammonia-producing organisms, and is of value in hepatic encephalopathy.
Dose: as laxative 20 mg daily mixed with food, together with 2 glasses of water. Dose in hepatic encephalopathy, 500700 inglkl; daily.
lactulose An osmotic laxative. See lactilol.
laevulose Fructose. A sugar sometimes given i.v. as an alternative to glucose.
in the brain by inhibiting the influx of sodium ions. It is used both as primary treatment and as additional therapy (often with sodium valproate) for seizures not fully controlled by other drugs.
Dose: 25 ing daily initially for 14 (lays, slowly rising to 100-200 nig daily. See data sheet for details of combined therapy. (Limictal). See page 136 and Table 15.
lanolin See wool fat.
lansoprazole An inhibitor of the enzyme 11, K’-AI’Pase (the proton pump) used in the treatment of peptic ulcer.
Dose: 30 ing daily for 4-8 weeks. (Luton). See orneprazole, page 162 and Table 27.
Lasser’s paste A stiffointment containing zinc oxide, starch and white soft paraffin with 2% salicylic acid. Used as protective in eczema.
latanoprost A prostaglandin alpha-analogue used once daily as eye drops (0.00596) in glaucoma. It increases the outflow of the aqueous humour, whereas other agents reduce its secretion. Continued use may cause changes in eye colour. (Xalantan). See page 138.
lenograstimV A recombinant form of the granulocyte colony stimulating factor (G–GSF) that governs the production of neutrophils. It is used as supplementary treatment in cancer chemotherapy to stimulate neutrophil production in drug induced neutropenia.
Dose: under expert supervision by s.,:. injection, in daily doses of 150 pg/m2 Until neutrophil count is satisfactory. Also used i.v. after hone narrow transplantation. (Granocyte). See filgrastim and rinolgraniostirn. See page 122 and Table 8.
61
lamivudine An antiviral agent that acts like zidovudine by inhibiting reverse transcriptase, an enzyme essential for DNA formation and viral replication. It is used in HIV infections.
Dose: 300 ing daily, preferably with food, and combined with a protease inhibitor. (Epivir). See page 144 and Table 19.
lamotrigine\” An anti-epileptic that alleviates the imbalance of neurotransmitters
letrozoleV A non-steroid inhibitor of aromatase, the enzyme that controls the conversion of testosterone to oestrogen. It acts as an anti-oestrogen and is used in advanced breast cancer that has not responded to tamoxifen or similar therapy. Dose: 2.5 mg once daily. Side-effects include musculoskeletal pain, arthralgia and hot flushes. (Fernara). See page 122 and Table 8.
leucovorin See folinic acid.

leuprorelin A synthetic hormone that indiandrogen and oestrogen production by inhibiting gonadotrophin activity. It is used in endonietriosis and
advanced prostatic cancer.
Dose: 3.73 rig by s.c. or i.m. injection every 4 weeks. Side-effects are impotence, flushing and local irritation. There may be an initial and temporary increase in pain. The injection site should be varied. (Prostap SR). See buserelin, goserelin, page 122 and Table 8.
levamisole A single-dose (150 mg) anthelmintic of value in round worm (Ascaris). It is also effective against hookworm (Ancylostoma and Necator). Dose: 2.5-5 mg1kg daily for 2-5 days.
levobunolol A beta-blocker used as eye drops 0.5% in glaucoma. (Betagaii). See carteolol.
levocabastine An antihistamine used as drops (0.05% twice a day in the symptomatic treatment of seasonal allergic conjunctivitis and rhinitis. (Livostin).
levodopa An amino acid that is converted to dopamine in the body. It is used in the treatment of Parkinson’s disease, which is associated with a reduction in brain
dopamine levels due to degeneration in the substantia nigra, thus causing an imbalance in the neurohorinonal system of the brain. Levodopa is essentially replacement therapy, but as an oral dose is metabolized to some extent in the peripheral circulation It is often given with art enzyme inhibitor such as benserazide or carbidopa. Combined therapy permits a larger dose of active drug to reach the cerebral tissues, and at the same time reduces some of the general side-effects of levodopa.
Dose: 125-300 mg initially, increased according to need and response. Side-effects include nausea and cardiovascular disturbances, but psychiatric side- effects may be (lose limiting. Close angle glaucoma is a contraindication. See page 160 and ‘I able 26.
lignocaine (lidocaine) A local anaesthetic widely used for infiltration anaesthesia as a 0.25-0.5% solution, usually with adrenaline, as well as for epidural, caudal and nerve block anaesthesia. It is the local anaesthetic present in many dental cartridges. A 2-4% solution is used for
surface anaesthesia, and a 2% gel is used to relieve the pain and discomfort of catheterization, but rapid absorption may cause side-effects. Lignocaine is also the drug of choice in the control of ventricular tachycardia following myocardial infarction. Dose: 100 mg as an i.v. bolus, followed by a dose of 4 mg/min by i.v. infusion for 3(t minutes, with subsequent doses of 2 inghnin. Side-effects include confusion, convulsions, bradycardia and I p hy oten- sion. (Xylocard). Emla cream contains lignocaine and prilocaine. It is used for local anaesthesia and to relieve the pain associated with injections, especially in children. It is applied under an occlusive dressing 1-2 hours before the injection.
lindane A pesticide used as a 1% solution for the treatment of scabies.
liothyronine (tri-iodothyronine) A thyroid hormone with it rapid action, an(] probably a precursor of thyroxine. It is given orally in severe hypothyroid conditions when a rapid action is necessary, and by injection in hypothyroid coma. Dose: 20-60 fag daily; 5-20 pg i.v.
0 ertroxin).
liquid paraffin A lubricant laxative and faecal softener.
Dose: la-mj, nil. Its extensive use is now
discouraged, as it may cause granulomatous reactions and reduce the absorption of fat-soluble vitamins.
lisinopril An ACE inhibitor similar to enalapril, but with it longer action that permits the use of a single daily dose. Dose: in the treatment of hypertension, (loses of 2.5 rig daily initially, slowly increased according to response up to 10-20 mg daily, occasionally up to 40 mg. In patients receiving diuretics, such Ilierapy should be withdrawn for 2-3 days before lisinopril therapy and resumed later if necessary. (Carace; Zesiril). See
page 148 and Table 21.
lithium carbonate Lithium carbonate and itratearc used for their mood-regulating action in the prophylaxis and treatment of mania and depressive illness, but the mode of action is not known. The therapeutic/ toxic range of lithium is very narrow, and continuous control of the plasma/lithium level is essential to avoid the many side-effects and hazards of therapy.

flumazenil A benzodiazepine antagonist used in anaesthesia to reverse the sedative effects of benzodiazepines.
Dose: 200µg initially by i.v. injection, with subsequent doses of 100 pg at I -minute intervals, up to a maximum of I mg. Further doses may be given by i.v. infusion if drowsiness returns, as the action of flumazenil is brief. ( Anexate).
flunisolide A potent corticosteroid used locally in the more severe forms of hay fever and other nasal allergies.
Dose: 1)), nasal inhalation, 50pg (2 sprays), 2 or 3 times a day, continued for 2-3 weeks, or longer if required. (Syntaris).
flunitrazepam A benzodiazepine with a hypnotic action used for the short-term treatment of insomnia.
Dose: 0.5-2 nig. Side-effects include drowsiness, ataxia and visual disturbances. (Rohypnol). See page 152 and Table 22.
fluocinolone A topically active potent corticosteroid. Used as cream, ointment or gel (0.00625-0.025%) in severe, inflamed, corticosteroid-responsive skin disorders. Excessive application should be avoided. (Synalar).
fluocino”ide A potent locally effective anti-inflammatory steroid similar to fluocinolone, used as cream, ointment or lotion (0.05%). (Metosyn).
fluocortolone A locally acting corticosteroid used as cream or ointment (0.25%) in severe, inflamed skin conditions. (Ultralanum).
fluorouracil A cytotoxic agent used in the palliative treatment of carcinoma of the breast and gastrointestinal tract and other solid tumours.
Dose: 15 ingft orally or by i.v. infusion weekly, up to a total dose of 12-25 g. Side-effects include alopecia and dermatitis, but haeniatotoxicity, severe gastrointestinal disturbance and haemorrhage may limit treatment. Fluorouracil is used locally as a 5% cream (Efudix) in malignant skin lesions.
fluoxetine An antidepressant that acts by selectively inhibiting the uptake of serotonin. Given in single daily doses of 20 mg. Dose: 60 mg daily are given in bulimia nervosa. Side-effects are gastrointestinal disturbances, dizziness and anorexia; rash is an indication of withdrawal. It should not be used with other drugs that influence serotonin uptake. (Prozac). See page 128 and Table 11.
flupenthixol A tranquillizer similar to fluphenazine and used in the treatment of schizophrenia with apathy and withdrawal. It also has an antidepressant action.
Dose: 6-18 ing daily initially, with subsequent adjustment according to need. It may cause some restlessness and insomnia. Dose by deep i.m. injection, 20-40 mg every 2-4 weeks. Dose in depression: 500 pg 31ngdaily.The side-effects are similar to those of chlorpromazine. (Depixol; Fluanoxol). See page 168 and Table 30.
fluphenazine An antipsychotic drug with the actions and uses of chlorpromazine, but with reduced sedative and anticholinergic side-effects, although extra-pyramidal symptoms may be increased. Dose: 2- 10 mg initially in schizophrenia adjusted up to 20 ing daily. In severe anxiety states 1-4 mg. For depot treatment, 12.5-100 ntg of the decanoate by deep i.m. injection every 12-14 days according to response. (Modecate; Moditen). See page 168 and Table 30.
fluorescein An orange-red dye; solutions have a strong green fluorescence. Used as eye drops (1-2%) for detecting corneal lesions, as areas of cornea denuded of epithelium stain green.
fluorometholone A corticosteroid used as eye drops (0.10%) for inflammatory conditions of the eye. (FML).
flurandrenolone A potent locally acting corticosteroid used as a cream or ointment (0.0125%) in severe skin disorders not responding to other therapy. (Haelan). An adhesive tape is used for small resistant dermatoses.
flurazepam A benzodiazepine hypnotic for
the short-term treatment of insomnia.

flurbiprofen A non-steroid anti-inflammatory drug with the actions, uses and side-effects of naproxen. It is used in the relief of pain and inflammation in rheumatoid and arthritic conditions, and in other
nitisculoskeletal disorders.
Dose: 150 mg daily, after food, increased tip to 300 mg daily if necessary. Suppositories of 100 nig are available. Care is necessary in peptic ulcer and in aspirin-sensitive asthmatic patients. (Froben). See page 165 and’I'able 29.
flutamide An androgen blocking agent that inhibits the action of androgens on target organs. It is used in advanced prostatic cancer not responding to other drugs, usually in association with goserelin or related agents.
Dose: 750 mg daily. Side-effects include gynacconiastia, and liver function should be checked. (Drogenil). See page 122 and Table 8.
folic acid A constituent of the vitamin B group. It is essential for cell division and the growth and development of normal red blood cells. The main therapeutic use is in the treatment of megaloblastic anaemias due to folic acid deficiency. Dose: 5 ing daily for 4 months initially;
ing weekly may be adequate after the haematological response has been obtained. Sometimes given with anti-epileptic drugs, as long-term therapy may cause a folic acid deficiency. Small doses are present in many iron preparations to prevent the inegaloblastic anaemia that may occur in later stages of pregnancy. It must not be used alone in pernicious anaemia, as it cannot prevent the degeneration of the central nervous system associated with that disease.
folinic acid A methotrexate antidote. It is given ai the end of a course of methotrexate to reduce the toxic effects on normal cells and in methotrexate-overdose. Dose: up to 120 mg over 24 hours by i.m. injection (or i.v.), with 60 mg orally for another 48-72 hours.
49
fluticasone A corticosteroid of increased potency. Used as a metered dose pump for the prophylaxis and treatment of seasonal allergic rhinitis and hay fever.
Dose: 100 pg (2 sprays) into each nostril mice a day in the morning. Maximum reliefmay not be obtained for 3-4 days. Systemic absorption extremely low. (Nixonaw.
fluvastatinV An inhibitor of the enzyme I I N46-CoA-reductase used in the treatment of hyperlipidaemia.
Dose: 20-40 ing daily in the evening. (Lescol). See page 146,’I'able 20 and atorvastatin, provastatin and ‘inivastatin.
fluvoxamine An antidepressant that acts by inhibiting the central re-uptake of serotonin. It is used mainly for maintenance treatment during depressive illness. Dose: 100-300 mg, daily in the evening; a steady plasma level is normally reached within 10-14 days. Side-effects after initial nausea may include somnolence, constipation and agitation. It should not be used with other drugs that increase scrotonin uptake, or with aminophylline or theophylline. (Faverin). See page 128 and Table 11.
follitropin A recombinant form of the follicle stimulating hormone used in some forms of infertility. It is given by injection in doses dependent on the degree of ovarian response. (Puregon).
formaldehyde A powerful but toxic germicide used mainly in the disinfection of rooms, and as’formalsaline’ (5% in normal saline) for the preservation of pathological specimens. Warts have been treated with a 3% solution.
formestane An inhibitor of aromatase, the enzyme that converts androgens to oestrogens. It is used in advanced postmenopausal breast cancer, as it has a cytotoxic action mediated by causing an oestrogen deficiency state.
Dose: 250 mg by deep intragluteal injection at intervals of 2 weeks, with variations of the injection site. Side-effect are rash, pruritus and occasional vaginal bleeding. Mentaron). See page 122 and Table 8.
foscarnet An antiviral agent for the treatment of sight-damaging cytomegalovirus retinitis in AIDS patients as an alternative to ganciclovir.
Dose: 60 mg/kg daily by i.v. infusion for 2-3 weeks, with subsequent infusion at a rate dependent on renal function. (Foscavir). See page 144 and,ribic ig.
fosfestrol A water-soluble derivative of stilboestrol. It is metabolized by the enzyme acid phosphatase to liberate stilboestrol in tissues rich in that enzyme, and so it is of value in prostatic carcinoma.
Dose: 1)), slow i.v. injection, 600-1200 rni, daily for 5 days or more. Oral maintenance dose: 120-360 nig daily. perinea) pain is a side-effect. (I lonvan). See page 122 and Table 8.
fosfomycin A phosphorus-containing antibiotic used mainly for infections of the lower urinary tract.
Dose: 3 g nightly after voiding the
bladder. Also used prophylactically before prostatectomy. Rash, nausea and diarrhoea are side-effects. (Monuril).
fosinopril An ACE inhibitor indicated in hypertension when standard therapy is ineffective or unsuitable.
Dose: 10 mg daily initially, adjusted after •1 weeks up to 40 nig according to need. It is eliminated by the liver as well as the kidneys, and may have some advantages in renal impairment. (Staril). See ACE inhibitors, page 148 and Table 21.
framycetin An antibiotic resembling neomycin in general properties. Used in eye infections as drops or ointment 0.5%. (Soframycin).
friar’s balsam Contains benzoin, storax, aloes, balsam of tolu. Official name Compound Tincture of Benzoin. See benzoin.
frusemide A loop diuretic with a powerful and intense action of short duration. Often effective in conditions no longer responding to thiazide diuretics.
Dose: 20-40 mg daily or on alternate days, or 20-50 mg i.ma or i.v. Much larger oral doses, varying front 250 nie, up to a single maximum dose of 2g may be required in renal failure and oliguria. Side-effects include nausea, diarrhoea and cramp. Masix). See page 141 and’Fable 18.
fusidic acid See sodium fusidate.
gabapentin An anticonvulsant used in the L11111101 of the partial seizures of epilepsy, although the mode of action is not yet clear. Dose: 300 mg initially, slowly increased to 1.2 g daily according to need. Drowsiness, tremor and weight gain are some side-effects. Withdrawal is with slowly reduced doses over 2-3 weeks. (Neurontin). See page 136 and Table I5.
gallamine A synthetic non-depolarizing (competitive) muscle relaxant.
Dose: 80-120 mg initially i.v. with small subsequent doses according to need and response. The action of the drug may be terminated by the injection of neostigmine, 2.5-5 mg, together with atropine, 0.5-1 mg. (Flaxedil). Now used less frequently as tachycardia is a side-effect.
gamolinic acid A derivative of linoleic acid present in evening primrose oil. It is said to be of value in atopic eczema.
Dose: 320-480 mg daily. It is also used in mastalgia (breast pain) in doses of
240-320 mg daily, but the response is slow (8-12 weeks). (Epogam; Ffarnast).
gammaglobulin See immunoglobulin.
ganciclovir An antiviral agent similar to aciclovir, but more toxic. It is used only in sight- and life- threatening infections with cytomegalovirus (CMV) in immunocompromised patients.
Dose: by i.v. infusion, 5 mg/kg every 12 hours for 14-21 days, with mainte nance (lose of 5 mg/kg daily. Later oral dose 3 g daily. The solution is very alkaline, and injection requires care. Regular blood counts are essential. (Cvnievene). See page 144 an(Frable 19.
G-CSF human urnan granulocyte colony stimulating factor. See filgrastim and lenograstim.
fusafungine An antibiotic with anti-inflammatory properties used for upper respiratory tract infections.
Dose: as aerosol spray 123 jig 5 boles  day. (Locabiotal).
Gee’s linctus A soothing cough linctus containing camphorated tincture of opium, oxymcl of squill and syrup of tolu.

Coeliac Disease
During World War 11, there was no bread to be had in the Netherlands and people were forced to eat tulip bulbs. ‘My mother roasted them,’ one survivor recalls, ‘and they tasted delicious then, because we were so hungry I suppose. I cooked some years later, just to taste them again, and they were absolutely disgusting.’
While most of the population was thin and unwell on this starvation diet, a few children were actually healthier than before. An observant Dutch doctor noted that these were the children who, before the war, had suffered from constant diarrhoea, fatigue, poor growth and muscle wasting. They were suddenly stronger and, his enquiries revealed, their diarrhoea had vanished. But when the food situation improved at the end of the war, all their old problems returned. By carefully experimenting with the diet of these patients, the doctor discovered that eating wheat and rye caused the symptoms. Subsequent research has revealed that both contain a collection of proteins, referred to as gluten, which are the source of coeliac disease.
Belly disease
Coeliac disease (or celiac disease) is an old name which simply means ‘belly disease’. It is derived from the Greek word for’belly’ — koilia. Once the cause of the symptoms became understood, a new name was devised — gluten-sensitivity enteropathy — but it has not really caught on. Other terms that you may come across are non-tropical sprue and coeliac sprue, based on the close resemblance of the symptoms to those of tropical sprue. This disease, found in those who live or have lived in the tropics, is probably caused by bacterial infection. There is no causal link with coeliac disease.
Symptoms
The symptoms of coeliac disease are:
• diarrhoea, with pale, bad-smelling stools
• in a few patients, constipation rather than diarrhoea, but this is very rare
• bloating and wind
• damage to the lining of the intestine. This is of a characteristic type: the complex folded structures (the villi) of the intestinal lining are destroyed. Additionally, huge numbers of immune cells are present.
• the loss of the villi results in failure to absorb nutrients from food (malabsorption) causing poor growth in babies, and weakness and weight-loss in adults.
• poor appetite, especially in babies. This can greatly reduce the diarrhoea.
Coeliac disease usually appears in babies during weaning, a few weeks after cereals are introduced, but it can also begin for the first time in adults. The tendency to coeliac disease is genetically inherited, so it runs in families.
Where coeliac disease runs in the family, another disease, dermatitis herpetiformis, is also likely to occur. Dermatitis herpetiformis has the same basic mechanism as coeliac disease but very different symptoms:
• an intensely itchy rash, sometimes with tiny blisters; the rash is symmetrically distributed on the buttocks, shoulders, scalp, and the outer surfaces of the knees and elbows
• the same characteristic damage to the lining of the intestine as seen in tests for coeliac disease, though generally less severe
• diarrhoea, in some cases, but not all. About 5% of those with coeliac disease actually go on to develop dermatitis herpetiformis. Most people have either one or the other.
Both diseases are caused by the same gene, which results in sufferers developing antibodies against one of their own proteins, an enzyme called tissue-transglutaminase. The job of this enzyme, which is found in the intestines, is to assist with the breakdown of gluten.
If no gluten is present, the enzyme does not arouse the interest of the immune system. It is the process of gluten digestion, in which a particular peptide is produced from gluten, that provokes the autoimmune reaction. (A peptide is any short length of protein chain, obtained from the complete protein chain by digestion.)
What seems to trigger the autoimmune reaction is this enzyme–peptide combination: the offending peptide, newly produced and still attached physically to the enzyme. There is something about the particular ‘chemical picture’ that this combination makes which outrages the immune system of individuals with a particular genetic make-up.
The impact of this autoimmune reaction on the intestinal lining is severe in coeliac disease, less so in dermatitis herpetiformis. What causes dermatitis herpetiformis is a particular type of antibody, called dimeric IgA, which is transported by the bloodstream from the gut to the skin. It is deposited in the skin all over the body, but for some reason only provokes inflammation in certain areas.
In rare cases, an IgE-mediated food allergy to wheat can co-exist with coeliac disease, making reactions more severe.
Secondary problems
Paradoxically, while the damaged gut lining of untreated coeliac disease makes a poor job of absorbing specific nutrients (e.g. iron and vitamins) in a form that the body can use, it also lets through far more intact, or partially digested, food molecules. These get into the bloodstream in such numbers that they can lead to idiopathic food intolerance (see p.74). Sensitivity to soya is a common problem, because it is so heavily used in gluten-free bread and other prepared food. Those with coeliac disease who have not improved fully, despite a strict gluten-free diet, often benefit from an elimination diet (see p. 194). This must be done under medical supervision.
Another possible effect of the intestinal damage is lactose intolerance (see p.79), producing a sensitivity to milk.
The frequency of schizophrenia is higher among those with coeliac disease than among the general population. Coeliacs not following a strict gluten-free diet are also vulnerable to other psychological problems. These might be linked to the effects of food-derived exorphins (see pp. 76-7) and other peptides on the brain. The increased permeability of the gut could play a part in this, allowing more exorphins to reach the bloodstream.
Diagnosis
A biopsy (see p. 92) is the only really reliable form of diagnosis. It is crucial that this is done before removing gluten from the diet, because the damage is repaired if gluten is avoided and the healing process is fairly rapid for some people (though in others it takes many months). If the intestinal lining reverts to a normal appearance quite quickly, an accurate diagnosis is never obtained, which can have serious consequences: if you or your child are coeliac, you need to know.
New blood tests can also be helpful in diagnosis, but they do not give the unequivocal result obtained with a biopsy.
Research from the United States suggests that coeliac disease is under-diagnosed in some countries compared to others – for example, Italy screens children routinely but the States does not. Some authorities suspect that there is a great deal of ‘hidden’ coeliac disease in the States, and this could be true in other countries as well. There is no routine screening of children in Britain.
The symptoms of coeliac disease are not always distinctive. Many cases are first detected when patients with rather non-specific symptoms are discovered, by a blood test, to be anaemic.
Treatment
There are no drug treatments for coeliac disease and avoiding gluten religiously is the only way to remain well. Those who are lax about their gluten-free diet may be more vulnerable to certain cancers of the digestive tract.
A strict gluten-free diet is not easy to follow (see p. 177). The most severely affected coeliacs are so sensitive to gluten that they react violently to even a tiny amount: this is known as coeliac shock and can be fatal.
A gluten-free diet is also the treatment for dermatitis herpetiformis, but at the outset the rash can be controlled with the highly effective drug dapsone.

Food Intolerance
The comments of those who have recovered from food intolerance after many years of ill-health are always memorable. ‘It’s like getting my life back again,’ said one woman. ‘I had actually forgotten what it felt like to be well,’ said another, ‘the effect of cutting out certain foods was just amazing.’
For most of those with food intolerance, the disease begins very subtly and gradually – first one symptom (persistent and unexplained diarrhoea, perhaps) then, some years later, another (migraine or headaches) and then, when a few more years have passed, another symptom (such as joint pain or muscle aches). Steadily increasing levels of irritability, `fuzzy-headedness’ or inexplicable tiredness may accompany this decline in health.
Most patients have no idea that all these symptoms are connected until they try an elimination diet, and everything clears up at once, quite dramatically. As one former sufferer described it: `Some of the stuff that got better – well, I’d been like that so long I thought it was just the way I was –grumpy and exhausted, and feeling terrible if I didn’t eat meals on time. It was an absolute revelation to feel completely OK again.’
What does ‘food intolerance’ mean?
In this book, food intolerance means any reaction to food where the immune system has no proven central role.
All the people I have described so far have idiopathic food intolerance, which means, food intolerance with no established mechanism – in other words, doctors can’t say exactly how it is caused. This is a highly controversial area.
The definition of food intolerance used in this book means that it also includes metabolic abnormalities, which do have a well-established cause. These are due to defective enzymes (see upper box on p. 75).
The question of what words mean is a key part of the debate over idiopathic food intolerance. At one extreme, you may come across doctors who call this problem ‘food allergy’, using the original meaning of the word ‘allergy’ (see p. 6). (Some of these doctors use terms such as delayed food allergy and masked food allergy, to point up the distinction from true food allergy, but not all do.) Using the word ‘allergy’ in this context causes a lot of aggravation and confusion, so the term ‘food intolerance’ has, for a long time, been widely accepted as a useful one that avoids unnecessary conflict.
You will also hear the term ‘food intolerance’ used to mean idiopathic food intolerance only – this is probably the most common usage. When the term is used in this way, metabolic abnormalities are being thought of as a separate entity altogether.
A new twist has recently been added to this long-standing wrangle over meanings. When mentioning food intolerance in their literature, some of the major medical organisations (those who dispute the very existence of idiopathic food intolerance) now say simply ‘food intolerance e.g. lactase deficiency’. To anyone familiar with this field, it looks suspiciously like an attempt to redefine ‘food intolerance’ so that it means nothing more than ‘metabolic abnormalities’. The idea seems to be that, if you deny a disease a name, it will go away!
In the medical wilderness
The main text of this article is about idiopathic food intolerance, a disease with a distinctly dubious reputation among doctors. Because it is so controversial, few doctors actually look at the evidence that it exists – which is in fact quite strong (see box on p. 77). Such evidence is simply ignored in most of what is written by the major medical organisations debunking idiopathic food intolerance.
This lack of medical recognition is very unfortunate for patients with idiopathic food intolerance, whose debilitating symptoms could be eliminated, rather than simply being treated (usually to little effect) with drugs.
This prejudiced attitude to idiopathic food intolerance also plays into the hands of those offering bogus diagnostic tests and phoney treatments, often at a very high price. These practitioners
– who have moved in to fill the gap left by conventional medicine
– are a considerable part of the problem, helping to give idiopathic food intolerance a bad name.
The waters are muddied even more by the fact that some people who believe themselves to have food intolerance are actually suffering from psychological problems, which they prefer to attribute to food. Many more have picked up on food intolerance as something rather glamorous to suffer from, inspired by all the media reports about food intolerance among celebrities. All these patients are a good source of revenue for the less scrupulous fringe practitioners and are unlikely, therefore, to be discouraged from their beliefs.
Fortunately there are enough conventional but open-minded doctors, often GPs, who have come to realise, through experience with their own patients, that elimination diets have a remarkable curative effect for some people. The ones who benefit are often the doctor’s ‘old faithfuls’ – those with long-term multiple symptoms, who have been referred to innumerable specialists and treated with all kinds of drugs, but who never get much better. The conventional view of such patients is that they have psychological problems that are being expressed as physical symptoms. This may well be true for some – but others have idiopathic food intolerance.
One of our enzymes is missing
Metabolic abnormalities are a distinct type of food intolerance. Unlike other kinds of food intolerance, metabolic abnormalities have a clearly understood cause: an enzyme that carries out a crucial task in the body’s metabolism is either missing or inept. The problem is generally caused by a defective gene and is therefore inherited.
The most common metabolic abnormality is lactase deficiency leading to lactose intolerance (see p. 79) — this may or may not be inherited. Other metabolic abnormalities include:
trehalase deficiency, lack of the enzyme which breaks down a substance in mushrooms and most other fungi, including yeast. galactosaemia, a defect in the enzyme which processes galactose, one of the sugars found in milk (cow’s or human). This is a serious disease and sufferers must avoid milk scrupulously.
fructose intolerance, which is extremely rare. Those affected have an unpleasant taste in the mouth on eating fruit and other sources of fructose, so avoidance is no particular problem.
phenylketonuria, also very rare. Those affected are usually identified early in life, by a routine blood test.
Is it just placebo effect?
Doctors who doubt the very existence of idiopathic food intolerance will say that people who recover on an elimination diet are just experiencing placebo effect — a psychological response that operates with any treatment, whether effective or ineffective, simply because people believe that the treatment will work. But this is to ignore certain facts:
• Placebo effect produces a fairly small improvement in most people — you have to be very suggestible to feel enormously better. By contrast, when people respond to an elimination diet (the standard method for diagnosing idiopathic food intolerance —see p. 194) they usually have a sudden and dramatic improvement.
• Most of those with idiopathic food intolerance have had it for years and tried all sorts of treatments. They have often experienced some small benefit from these, probably placebo effect. When they try an elimination diet, they have a response that is in a completely different league.
• The idea that all the different symptoms are linked has never occurred to many people who try an elimination diet — they are often trying it for just one symptom, and are staggered when everything clears up. Placebo effect relies on expectation.
• Placebo effect doesn’t last very long — it fades over the ensuing weeks and months. Avoiding the culprit food usually produces a lasting improvement for those with idiopathic food intolerance.
Symptoms
The symptoms of idiopathic food intolerance come on slowly after eating the offending food, and the foods to blame are often those eaten very regularly, such as wheat or milk. Consequently, the symptoms from one meal tend to overlap with those from the previous meal and people with idiopathic food intolerance are more-or-less unwell for most of the time. It Is usually not obvious that food is at fault.
All the symptoms of idiopathic food intolerance are common ones that can be caused in other ways. And no two patients have exactly the same set of symptoms.
(As far as doctors are concerned, neither of these attributes gives the disease a respectable air.)
These are some of the symptoms commonly reported:
• headache or migraine
•diarrhoea, sometimes with bloating and wind; this is often diagnosed as irritable bowel syndrome (IBS)
• in children, stomach aches
• occasionally constipation
• nausea and indigestion
• joint pain
• aching muscles
• a constantly runny or blocked nose (this could be perennial allergic rhinitis linked to food – see p. 68)
• glue ear (see p. 29)
• fatigue and a general feeling of vague ill-health.
Asthma and eczema, triggered by specific foods (see p. 68), can also be part of the picture.
In babies, colic is often caused by food intolerance, including foods the mother is eating which come through into the breast milk in tiny amounts (see p. 202).
Less common symptoms include:
• recurrent mouth ulcers
• stomach or duodenal ulcers
• chronic urticaria (see pp. 50-53)
• swelling (angioedema).
The following diseases have also been linked to idiopathic food intolerance in some patients:
• Crohn’s disease
• palindromic rheumatism (intermittent episodes of joint inflammation)
• rheumatoid arthritis.
Psychological problems such as depression, anxiety, or hyperactivity in children can sometimes be due to food (see p. 80) but it is rare for such psychological effects to occur without any physical symptoms.
Remember that every single one of these symptoms and conditions can be caused in some other way. However, the constellation of migraine/headache, joint pain and diarrhoea is highly characteristic of idiopathic food intolerance.
How might intolerance be caused?
No one knows how idiopathic food intolerance is caused. There are probably many factors involved, with a slightly different mix of factors in each patient. This would help to explain why the symptoms are so extraordinarily varied, with no two sufferers exactly alike.
Although symptoms accumulate over the years, some people can in fact pinpoint the moment when their problems began. ‘I had this terrible bout of diarrhoea from eating too much melon. I lived near a farm and they were free, because of a glut, so I just gorged myself on them. Although I was over the diarrhoea in a couple of days, I was never what you’d call “regular” after that, and the least thing would upset me. Eventually the doctor said it was irritable bowel syndrome. When the other problems began, ages afterwards – headaches and hypoglycaemia and fatigue – it seemed like something quite separate. I never associated them in my mind with the diarrhoea.’
Bad diarrhoea can clear the intestines of their beneficial bacteria, known collectively as the gut flora (see p. 204), and this is probably what initiates food intolerance in such cases. Large doses of antibiotics (as are sometimes given before an operation, e.g. a hysterectomy), or prolonged and repeated courses of antibiotics, given for glue ear or acne, can also disrupt the gut flora and lead to food intolerance. A study of hysterectomy patients has shown that antibiotic treatment before the operation tends to result in irritable bowel syndrome – a common symptom of idiopathic food intolerance – afterwards.
A few interesting observations suggest that minor metabolic abnormalities – a defect in certain detoxification enzymes – may sometimes play a part in idiopathic food intolerance. This is especially likely where there is intolerance to food additives, or where there are behavioural symptoms (such as hyperactivity) or symptoms involving the nervous system (such as migraine).
A third factor that could play a part for some patients are food-derived exorphins. These are fragments of proteins (called peptides) produced by the digestion of food proteins. They happen, probably by pure coincidence, to resemble the substances called endorphins that we all produce for ourselves. Endorphins
are our internal painkillers. They modify nerve impulses in the body and brain, reducing sensations of pain, and improving the sense of well-being. The receptors to which they bind are the same receptors that bind morphine and heroin - it is the intensive stimulation of these receptors that makes these drugs so effective.
Food-derived exorphins may sound like the stuff of science fiction, but they have actually been demonstrated in the digestion products of wheat and milk. They may exist for other foods as well. They are nowhere near as strong as morphine, but do seem to improve mood.
These exorphins may explain the strange observation (made repeatedly, by a great number of initially sceptical doctors) that patients with idiopathic food intolerance often eat huge amounts of their offending food, and ‘can’t live without it’. Often they eat the food several times day, sometimes at every meal. With a ubiquitous ingredient like wheat or milk, this is not particularly difficult - wheat cereal and milk for breakfast, a cheese sandwich at lunchtime, pasta with a creamy sauce for supper, a milky drink and biscuits at bedtime.
Any of these abnormalities is likely to be just one factor in a multi-factorial disease.
Diagnosis
Unfortunately there are no simple accurate tests for idiopathic food intolerance. The kind of tests you may see offered commercially (in advertisements in health magazines for example) are very inaccurate, and a waste of money. Consequently, the only way to diagnose idiopathic food intolerance is through an elimination diet, in which you cut out all the foods you commonly eat, and then -if you get better - test them one by one.
It sounds easy but it isn’t, so make sure you read all the instructions for doing the diet before you start (see pp. 194-7). You should also see your doctor and get his or her approval. Some symptoms - such as severe diarrhoea or headaches -should be investigated by conventional methods first, in case there is some serious underlying cause.
The first step in diagnosis is to decide if a food really is the cause of the symptoms, and the second step is to identify the food or foods concerned.
The first step is crucial. One of the problems with the diagnostic tests that are advertised - such as those using samples of hair or blood - is that they begin with the second step. In other words they assume that food is the problem (see p. 93).
When it comes to the second step, remember that although common foods are often the culprits, almost anything that is eaten can cause idiopathic food intolerance. Every patient with this problem is different in the foods they react to.
Treatment
Avoidance of the food is usually the best treatment for idiopathic food intolerance - however most people do not have to avoid their problem foods for ever. After a while - it could be six months or it could be three years - you can usually go back to eating it again, but in moderation. You must never start eating the food in large amounts again, and it is best not to eat it every day - certainly not at almost every meal, which is the usual pattern for cow’s milk and wheat in the Western diet.
If you find the restrictive diet too difficult, you could try desensitisation treatment (see pp. 210-13). This can work very well.
The patients who should avoid the culprit food indefinitely are those with Crohn’s disease and rheumatoid arthritis: a severe and irreversible relapse can occur otherwise.
The evidence
The evidence for idiopathic food intolerance is more substantial than its opponents would have you believe.
One very well-conducted and interesting study involved children with severe migraine who were investigated by a research team at Great Ormond Street Hospital in London. These are children who are very difficult to treat successfully by normal means. On an elimination diet, 88% of those children got better — an astonishing number. Not just their migraine, but all sorts of other symptoms as well, including aching limbs, runny noses, asthma, eczema, diarrhoea, wind, mouth ulcers and hyperactivity. Some of these children also had epileptic fits, and even this symptom cleared up on the diet, recurring when culprit foods were tested.
A notable feature of this study is that, of the five researchers involved, four were deeply sceptical at the outset. Their report notes that they ‘embarked on this study believing that any favourable response, such as that claimed to substantiate the dietary hypothesis, could be explained as a placebo response. The positive double-blind controlled trial… provides clear evidence that a placebo response was not the explanation.’
Other studies with good scientific credentials have demonstrated a role for idiopathic food intolerance in adults with migraine, and for sufferers from irritable bowel syndrome and Crohn’s disease. There are also good studies of individual patients with rheumatoid arthritis and palindromic rheumatism (an episodic form of inflammatory arthritis) who have responded dramatically to avoidance of a particular food. Some of these patients were given several double-blind challenges and showed changes in certain immunological tests, as well as joint symptoms, when challenged with the offending food. This suggests that the immune system could be playing some part in these food reactions.