Posts Tagged ‘toxic effect’

Drug compliance
It must be admitted that relatively few patients leave the consulting room with a clear idea of the nature and dose of the prescribed medication, partly as a result of fear of th
and partly because of the difficulties of understanding complex therapy. Here, nurses can play a valuable part in reducing difficulties and misunderstandings, particularly when dealing with the elderly and/or confused patient, and it is often helpful to ask patients to repeat the directions that they believe they have been given. Misunderstandings and errors can then be cleared
up at an early stage. The containers of the dispensed medicines should bear not
only the name of the drug, but also useful additional information such as The Heart Tablets’ or ‘The Water Tablets’. Vague directions should be avoided: whenever possible definite times for administration of drugs should be arranged. Such timing can be linked with some regular activity, such as a meal time, or a favourite TV programme may be used as a memory aid for regular dosing. With multiple therapy, patients should be encouraged to set each day’s dose aside, so that a double dose of a drug will not be taken by forgetfulness. Patients should be advised that the occasional missed dose is not always important, and a missed dose should not be made up by taking a double dose later on.
Although regular dosing is important in securing patient compliance, many modern drugs have relatively long half-lives so the regular administration of full doses for long periods may lead to overdose. The ideal dose depends on many factors, including absorption, metabolism, transport and excretion, but in many cases the margin of safety is fairly wide. In the elderly, however, reduced renal efficiency may lead to the gradual accumulation of a drug with insidious toxic effects. Many elderly patients, for example, on digoxin, may become overdivitalized because of poor metabolism and excretion of the drug. It is by no
means unknown for elderly and confused patients, once admitted to hospital for observation, to make an apparently surprising recovery from an illness that was basically due to over-medication, often as a result of following blindly a misunderstood drug regimen. It is here that the community nurse has an exceptionally valuable part to play in ensuring regular and accurate medication, and reporting any incipient signs of overdose or side-effects.
Ail increasing problem of current therapy is patient compliance with prescribed treatment. It is easy for a doctor to prescribe, but to ensure that the patient takes the prescribed drugs in the right dose is a very different matter. The magnitude of the problem has increased with the rise in multiple therapy, and the reluctance on the part of some doctors to prescribe mixed products.

tiaprofenic acid A non-steroidal analgesic and anti-inflammatory agent with the actions, uses and side-effects of related NSAIDs such as naproxen.
Dose: 600-800 nig daily. Mild oedema may occur with extended treatment. Peptic ulcer and asthma are contraindications. Severe cystitis is an occasional side-effect. It should not be given to patients with urinary tract disorders, and should he withdrawn at once if any
urinary symptoms develop. (Surgarn). See Page 165 and Table 29.
t1bolone A compound described as an gonadomimetic steroid as it has oestrogenic and progestogenic properties. It is used to control the vasomotor symptoms of the menopause, including those surgically induced as well as those occurring naturally.
Dose: 2.5 ing daily for some months. Similar doses in the prophylaxis of osteoporosis. Side-effects are headache, dizziness and vaginal bleeding. Treatment should be withdrawn if any thromboembolic symptoms or jaundice appear. (1,ivial).
Dose: 400 nig as a single daily dose for 12 weeks, to be taken with water at least 2 hours before or 2 hours after meals. Antacids and milk should be avoided. The improvement in serum alkaline phosphatase activity may persist, and a second course needed only after an interval of at least 6 months. Gastrointestinal side-effects are common, but renal function should be monitored regularly. (Skelid).
timolol A beta-andrenergic blocking agent of the propranolol type, used in the control of angina and hypertension. Dose: 10-60nigdaily. In the prophylactic t i catment of migraine, 10-20 ing daily. (,’are is necessary in bradycardia, cardiac insufficiency and bronchial disease. It is also of value as eye drops (0.25%-0.5%) in simple chronic glaucoma, as it reduces infra-ocular pressure by reducing the formation of the aqueous humour. (Betim; Blocadren; Timoptol). See pages 148 & 154, and Table 21.
tinidazole A drug similar to metronidazole, and used mainly in the prophylaxis and treatment of anaerobic infections and anioebiasis.
Dose: 2 g initially, followed by I g daily for 5 days. A single oral (lose of 2 g is given 12 hours before abdominal surgery, and a similar single dose is given in amoebiasis and giardiasis. Side-effects are nausea, vomiting and diarrhoea. A disulfiram-like -like reaction may occur if alcohol is taken. ( Fasigyn).
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ticarcillin An antibiotic with an increased activity against Pseudomonas aeruginosa. In pseudomonal septicaemia, combined treatment with an aminoglycoside anti biotic such as gentamicin may evoke an increased response.
Dose: 15-20 g daily by slow i.v. injection or infusion in systemic infections; 3-4 g daily by i.m. injection in urinary infections. (Ticar). It is sometimes given together with clavulanic acid as Timentin, but it delayed post-treatment reaction with Tinientin is cholestatic jaundice, thought to be due to clavulanic acid.
tiludronic acid A bisphosphonate that inhibit., (fie [)one resorbing activity of osteoclasts, and so reduces the excessive demineralization of bone that occurs in Paget’s disease.
tinzaparin A low-molecular weight heparin ti,cd in the prevention ofthromboembolism.
Dose: by s.c. injection 2500-3000 units daily for 7-10 days. It is also used to prevent clotting in haemodialysis apparatus. (Innohep; Logiparin). See dalteparin and enoxaparin. With these products laboratory control is not necessary.
tioconazole An antifungal agent used in
tines infections of the nails by the
extended application of a 289/6 solution. Treatment for 6 months or more may be necessary. (Trosyl).
titanium dioxide A metallic oxide, similar to zinc oxide, with mild astringent properties. It is present in some sunburn protection preparations.

tizanidine A central alpha, receptor agonist use([ in the spasticity associated with multiple sclerosis and spinal injury. Dose: 2 ing weekly, increased according to response up to 24 ing daily. Monitor liver function monthly for 4 months. (Zaiiallex).
tobramycin An aminoglycoside antibiotic with the actions, uses and side-effects of gentamicin, but considered to be more active against Pseudomonas aerugi . nosa. Dose: 3-5 nig1kg daily by i.m. injection or i.v. infusion. It may be given together with a penicillin or nictroniclazole in serious mixed infections. Care is necessary to avoid the ototoxic and nephrotoxic effects of aminoglycosides. (Nebcin).
tocainide An anti-arrhythmic agent similar in action to lignocaine. It is a powerful drug, and may cause severe blood dis(urhances, and its use is largely restricted to the control of life-threatening arrhythmias not responding to other drugs.
Dose: 1.2-2.4 g daily. Blood counts during treatment are essential. Side-effects include bradycardia, hypotension, rash, tremor and aplastic anaemia. (Tonocard).
tocopherol A synthetic form of vitamin E.
tolazamide An oral hypoglycaemic agent related to tolbutamide, with similar actions, uses and side-effects.
Dose: 100-250 mg daily, increased if necessary up to a maximum dose of I g daily. (Tolanase). See page 131 and Table 13.
tolbutamide A sulphonylurea used like Jilorproparnicle in the treatment of maturity-onset diabetes, but it has a shorter action, and twice-daily doses are usually necessary. It is effective only when some insulin-secreting cells of the pancreas are still functioning, and a return to insulin therapy may be necessary during illness and infection. Tolbutarnide is not suitable for the treatment of juvenile or severe diabetes.
Dose: 0.5-2 g daily. Side-effects include hypoglycaemia, poglycaernia. rash, Jaundice and blood dyscrasias, but are uncommon with low doses. (Rastinoo). See page 131 and
Table 13.
tolcapone An inhibitor of the enzyme concerned with the biosynthesis of dopamine. It is used with other drugs in the
treatment of parkinsonism in initial doses of 100 mg 3 times a day. Side-effects are dyskinesia, nausea and sleep disturbances. (Tasmar). See page 160 and Table 26.
tolfenamic acid A non-steroidal anti-inflammatory drug (NSAID) but exceptional in being used in the treatment of migraine, on the basis that prostaglandins are involved in the pathology of migraine. Dose: 200 mg at the onset of an attack, repeated once after 2-3 hours if necessary. Close monitoring is required if anticoagulants also given; caution in peptic ulcer. (Clotani). See page 154 and Table 23.
tolmetin An anti-inflammatory analgesic agent used in rheumatoid and mUSCUIOskeletal conditions. As with related non-steroidal anti-inflammatory drugs
(NSAIDs) it may cause gastrointestinal disturbances in some patients, and should be taken after food. Hypersensitivity reactions may occur occasionally.
Dose: 0.6-1.8 g daily. (Tolectin). See page 163 and -Fable 29.
topiramateV A new anti-epileptic that differs chemically from related drugs. It is used as adjunctive therapy in partial seizure patients not adequately controlled by standard treatment.
Dose: initial (lose 100 nig daily, slowly increased at weekly intervals as required up to 800 mg daily. Patients receiving digoxin should be monitored. Not recommended for children. (Topaniax). See page 136 and Table 15.
topotecanV A new advance in cancer chemotherapy is the use of topoisomerase inhibitors. Topoisomerase I is necessary for DNA replication, and topotican acts by binding with super-coiled DNA and so preventing further DNA development. Dose: 1.5 mg/n’ by i.v. infusion daily for 5 days under expert supervision. Side-effects are myelosuppression and severe neutropenia. (Hycamptin). See page 122 and Table 8.
torasemide A loop diuretic of the
IrLISCII)i(IC type.
Dose: in oedema, 5-20 ing once daily; in pulmonary oedema 10-20 mg daily by slow i.v, injection but much larger doses are sometimes necessary. In hypertension. 5-20 mg daily. (Torero). See page 148 and Table 21.

toremitene’v” An anti-oestrogen used in h0i 11 im ie- dependent metastatic breast cancer.
Dose: 60 mg as a single daily dose. Side- effects are linked with the mode of action
aninclude hot flushes, dizziness and
sweating. Care is necessary in severe hepatic deficiency, angina and cardiac weakness. (Fareston). See page 122 and Table 8.
trannadoW An analgesic used in the short-tan) treatment of moderate to severe pain. It has reduced affinity for opioid receptors, and the action may be mediated by inhibiting the neuronal re-uptake of noradrenaline and related amines. Dose: 300-400nig; in severe pain it may he given by i.m. injection or i.v. injection/infusion in closes of 50- 100 ing 4-6-hourly. (Tramake; Zamadol; Zydol).
trandolapril An ACE inhibitor used in mild io moderate hypertension.
Dose: 500 jig daily initially, increased at intervals of 2-3 weeks up to 1-21ng once daily. If hypotension occurs, reduce supportive therapy before lowering the trandolopril dose. Prophylactic dose after myocardial infarction 500 Vg-4 mg daily. Diuretic therapy should be stopped before starting with trandolapril, to reduce the risks of initial hypotensive side-effects. (’are with monitoring in patients with renal and hepatic impairment. (Gopten; Odrik). See page 148 and Table 21.
tranexamic acid An antifibrinolytic agent used to check haemorrhage after prostactectomy, in surgery generally and in the control of menorrhagia.
Dose: 2-8 g daily; 3 g daily by slow i.v. infection. Side-effects are nausea, diarrhoea and dizziness. (Cyklokapron).
tranquillizers These drugs were once Separated into the major tranquillizers, represented by chlorpromazine, and the minor tranquillizers exemplified by diazepam, but are now often referred to as antipsychotic drugs and anxiolytics respectively. The antipsychotics are used mainly in the control of disturbed patients, and in schizophrenia, although they have some anti-anxiety properties, and long-term treatment is often necessary. The anxiolytic drugs are intended mainly for the short-term treatment of acute anxiety states, as extended use may
cause dependence. See pages H 7 & 168, and Tables 5 & 30.
Transiderm-Nitro A medicated patch containing glyceryl trinitrate designed to have an action over 24 hours in the prophylaxis of angina.
tranylcypromine A monoamine oxidase inhibitor (MACI), of use in severe depression not responding to other drugs. Dose: 20 nig daily initially, increased to .50 ing daily or more according to need. The use of tranylcypromine requires care, as the drug has a stimulant action that may complicate therapy, and phenelzine may be preferred. Side-effects are dizziness, dry mouth and insomnia. Liver damage may also occur, and a hypertensive crisis with throbbing headache requires withdrawal of the drug. Hyperthyroidism is a contraindication. (Parnate). See page 128 and Table 11.
trazodone An antidepressant chemically distinct from other drugs with a similar action, and with reduced anticholinergic and cardiovascular side-effects. It is
indicated mainly in depression associated with anxiety when a sedative action is also required.
Dose: 150-300mgd;iily.’['Iieside-effects are those of the tricyclic antidepressants such as amitriptyline. (Molipaxin). See page 128 and’I'able 11.
treosuffan A cytotoxic agent related to busulphan, but used mainly in ovarian cancer.
Dose: I g daily for 28 days, repeated after a 4-week rest period; 5-15g by i.v. injection at intervals of 1-3 weeks. In all cases the (lose is adjusted according to the
degree of bone marrow depression that occurs. Other side-effects are those of cytotoxic drugs generally. Extravasation causes pain and local tissue damage. See page 122 and Table 8.
tretinoin A derivative of vitamin A. It is used locally for acne (Retin-A) and also for the treatment of photodamage to the skin (Retinova). A new use is the induction of remission in acute promyelocytic leukaemia.
Dose: 22.5 trig/m2 twice daily with food. Combined therapy may reduce the risk of relapse (Vesanoid).

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.
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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.

cytarabine A cytotoxic agent that prevents cell development by inhibiting the formation of nucleic acid. It is used mainly in the control of acute mycloblastic leukaemia.
Dose: 0.5-3 mg/kg daily by i.v. or s.c. injection. Close haematological control is essential as the drug is a powerful myclodepressant. Other side-effects are those of the cytotoxic drugs, generally, but fever, myalgia and bone pain may also occur. Alexan; Cv cos: r).
Dose:    nig/kg, daily for 10 days, repeated after 4 weeks. Side-effects are severe nausea, bone marrow depression and an influenza-like syndrome. The drug should be handled with care, as it is a tissue irritant. (DTIC).
dactinomycin See actinomycin D.
dalteparin A low-molecular weight heparin given by s.c. injection for pre- and postoperative thrombo-embolic prophylaxis. Dose: 2500 units daily for 5 (lays. (Fragmin). See enoxaprin and tinzaparin.
cytotoxic drugs A term applied to drugs that can kill cancer cells. In practice, many factors influence their therapeutic value. They are rarely selective, and therapeutic doses usually have a toxic effect on sonic normal cells. They may attack cancer cells at different stages of development, as actively dividing cells are more susceptible than resting cells. They may not reach the cancer cells in adequate concentration, or resistance to the drug may develop. The dose may also depend to some extent on the patient’s tolerance of the drug, and combined treatment with two or more drugs may have the advantages of increased potency with reduced toxicity. All cytotoxic drugs, with the exception of bleomycin and vincristine, bring about a depression of the bone marrow, which may be severe, and some degree of hair loss, which is usually reversible. Severe nausea and vomiting are also common, and early use of powerful antiemetics is essential. Many cytotoxic agents are tissue irritants, and with i.v. treatment great care must be taken to avoid extravasation, as severe local tissue damage can occur. See alkylating agents and antimetabolites. See page 122.
clacarbazine A cytotoxic drug that appears to depress purine metabolism and the formation of DNA. It is used mainly in malignant melanoma, and in combination with other agents it is of value in other malignant conditions.
clanazol A derivative of ethisterone that inhibits the release of pituitary gonadotrophins. Used in conditions such as endometriosis and gynaecomastia. Dose: 200-800 ing daily, starting during menstruation. Side-effects are nausea, dizziness, rash, flushing and hair loss. Care is necessary in cardiac, renal or hepatic impairment, and in epilepsy and diabetes. (Danol).
danthron A synthetic anthraquinone laxative used mainly for constipation in the aged, and in drug-induced constipation in the terminally ill. Not suitable for routine use by other patients.
Dose: given in doses of 25–25 mg as codanthramer, and acts within 6-12 hours. the urine may be coloured red.
dantrolene A skeletal muscle relaxant that acts on the muscle fibre, and not at the myoneural junction. The action may be linked with an interference with the movement of calcium ions. It is used in the severe and chronic spastic states that occur after stroke, spinal cord injury, and in multiple sclerosis.
Dose: 21 ing daily initially, increased at weekly intervals up to a maximum of 400 mg daily, as the response is slow and May be inadequate. The side-effects of weakness and Gangue are mild, and often transient, but liver function tests during treatment are essential. Dantrolene is also of value in malignant hyperthermia, a rare but serious complication of anaesthesia, and is given in doses of I mg/kg by i.v. injection as soon as the condition is diagnosed,

dapsone A sulphone compound used in the ti,atnient of leprosy.
Dose: 25-400 mg orally twice weekly and continued for some years. Resistance to dapsone may occur, and combined treatment with clofazimitic and rifarnpicin may lie necessary. Dapsone is sometimes given with pyrimetharnine in chlotoquine-resistaut malaria. Side-effects are nausea, rash, neuropathy and myelodepression.
duration of action. Used in the diagnosis and control of diabetes insipidus, and in the treatment of nocturnal eneuresis. Dose: 10-20pg intranasally once or twice
a day; 1-4 pg daily by injection. IMAM.
desoxymethasone A corticosteroid, for local application in acute inflammatory and allergic skin conditions. Used as oily cream 0.25%. (Stiedex).
daunorubicin See doxorubicin.
debrisoquine An adrenergic neurone blocking agent with the actions, uses and side-effects of guanethidine, except that it is less likely to cause diarrhoea. It is used mainly in resistant hypertension, in association with other drugs. (Declinax).
See page 148 and Table 21.
deflazacort A glucocorticoid with the actions and uses of related drugs, and comparable in activity with prednisolone. Dose: initially in acute conditions up to 120 mg daily; maintenance dose 3-18 mg daily. (Calcort). See hydrocortisone, page 55 and Table 36.
demeclocycline An antibiotic with the actions, uses and side-effects of tetracycline, but more likely to cause photo-allergic reactions.
Dose: 600 mg daily. Used occasionally in hyponatraemia due to overactivity of the antidiuretic hormone. (Ledermycin).
desferrioxamine A chelating agent that combines with iron salts to form a soluble non-toxic complex. Of great value in acute ferrous sulphate poisoning in children. Dose: 2 g immediately by i.m. injection, together with gastric lavage (2 g of desferrioxamine/1) followed by a single oral dose of 10 g. It may also be given by continuous i.v. infusion, 15 mg/kg hourly up to a maximum of 80 mg/kg. It may cause hypotension if the infusion is given too rapidly. It is also useful in the treatment of iron-overload caused by repeated blood transfusions, and for aluminium overload in patients On dialysis. (Desferal).
desflurane An inhalation anaesthetic
similar to CuflUrane. (Suprane).
desmopressin A derivative of vasopressin, with increased potency and longer
dexamethasone A potent synthetic corticosteroid, with reduced salt-retaining properties. Useful in all conditions requiring systemic corticosteroid therapy (except Addison’s disease), including inflammatory and allergic disorders, shock, cerebral oedema and adrenal hyperplasia.
Dose: 0.5-2 mg daily up to a MaXiMUM Of’ 15 mg daily; in shock, 5-20 mg by slow i.v. injection or infusion; in cerebral oedema, 10 ing initially by i.v. injection, followed by 4 mg i.m. 6-hourly. Dexamethasone is also given by infra-articular injection for local inflammation of joints in doses of
0.4-4 mg. It is also used as eye drops (0.1%)
in uveitis, but care is necessary with prolonged treatment as with some patients a ’steroid glaucoma’ may be precipitated. (Decadron). See page M and Table 36.
dexamphetamine sulphate A central nervous system stimulant. It is used in the treatment of narcolepsy and, paradoxically, it is sometimes useful in hyperkinesia in children.
Dose: in narcolepsy, 20-60 mg daily; in hyperkinesia 2.5 mg initially, slowly increased up to a maximunl’of 20 mg daily. Side-effects are insomnia, anorexia and agitation. Dependence and tolerance may occur early. (Dexedrine).
dextran A blood-plasma substitute
obtained from sucrose solutions by bacterial action, and used as solutions of varying molecular weight (dextran 40, 70). Dextran 70 is used as a blood volume expander by i.v. injection in some cases of shock; dextran 40 is used mainly to improve postoperative peripheral circulation, reduce blood viscosity, and to prevent thrombo-embolism. Care must be taken to adjust dose to avoid overloading the circulation. Any blood-matching should be carried out before giving dextran. (Gentran; Macrodex; Rheomacroclex).