Posts Tagged ‘therapeutic value’

vasodilators Traditional vasodilators used in the prophylaxis and treatment of angina include glyceryl trinitrate and other nitrates. They have a general effect on the venous system but newer and more selectively acting antihypertensive drugs are the betaadrenoceptor blocking agents represented by propranolol, and the calcium channel blocking agents such as nifedipine. Other vasodilator drugs are the alpha-adrenoceptor blocking agents (indorarnin, prazosin) and the ACE inhibitors (captopril). Cerebral vasodilators are represented by isoxsuprine. Peripheral vasodilators include cinnarizine and thymoxamine. See pages 114 & 148.
vasopressin A preparation of the blood pressure- raising and antidiuretic factors of the pituitary gland. It has been used in doses of 5-20 units twice daily by s.c. or i.m. injection in diabetes insipidus, but has been largely superseded by demopressin. (Pilressin).
vecuronitim A non-depolarizing muscle relaxant of the rocuronium type. It has a medium duration of action, with the advantage of not causing histamine release. Dose: 80-100fLgjkg1min initially, with supplementary doses as required. (Norcuron).
venlafaxine An antidepressant that inhibits the re-uptake of both serotonin and nor-adrenaline.
Dose: in depressive illness, 75 mg daily, rising if necessary after some weeks to 150 ing daily, or exceptionally to 375 mg daily. Prolonged treatment is necessary for an adequate response and reduce potential relapse. Reduced doses are given in hepatic disease and lite elderly. Care is necessary in epilepsy, and before and after morloaniine oxidase inhibator (MAGI) therapy. Many side-effects have been noted, but any skin reaction should be reported to the prescriber. (Ffcxor). See page 128 and Table 11.
Dose: 120-480 mg daily according to the condition and degree of response. In severe arrhythinias, 5-10 mg i.v. under ECG control. Contraindicated in bradycardia, heart failure and heart block. Side-effects include nausea, hypotension and heart block. It should be used with caution in a patient already receiving a betaadrenoceptor blocking agent. (Cordilox; Securon). See page 148 and Table 21.
vigabatrin A new anti-epileptic drug. GABA (a gamma aminobutyric acid) is an inhibitor of neurotransmission, and epileptic seizures may be linked with a GABA deficiency. Vigabatrin has an inhibitory action on the GABAmetabolizing enzyme, and so indirectly permits a rise in the brain level of GABA. It is used in the treatment of epilepsy not responding to other anticonvulsants. Dose: 2 g daily initially, with adjustments up to 4 g daily together with current antiepileptic therapy. Side effects are numerous, and include drowsiness, fatigue, dizziness and weight gain. Sudden withdrawal is inadvisable. (Sabril). See page 136 and Table 15.
viloxazine An antidepressant with the general action, uses and side-effects of amitriptyline, but with a reduced sedative activity. It is given in depression associated with apathy, and in the depression of epilepsy.
Dose: 150-400 mg daily. It may increase the action of phenytoin and antihypertensive agents. (Vivalan). See page 128 an(] Table 11.
vinblastine An alkaloid of periwinkle that has cytotoxic properties. It is used in the control of acute leukaemias, lymphomas and other malignant conditions, and in mycosis fungoides.
Dose: 100 ltrjkg weekly i.v., increased by 50 pg/ki; weekly, up to 500 µg/kg weekly according to response. Side-effects include myclosuppress.ion, neurotoxicity and abdominal disturbances. The drug should be handled with care as it is a tissue irritant. (Velbe). See page 122 and Table 8.
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verapamil A calcium channel blocking agent that reduces the movement ofcalciurn ions in cardiac tissues. It reduces the oxygen demand as well as the contractility of the myocardium, and it is used in angina, arrhythmias and hypertension.
vincristine A vinca alkaloid with the action and uses of vinblastine, but much less likely to cause myclodepression. It is used mainly in the treatment of acute
leukaemias in children, Hodgkin’s disease and other malignant lymphomas.

Neuromuscular side-effects may limit the dose. Other side-effects are abdominal disturbance and alopecia. The injection of the drug requires care as it is a tissue irritant. (Oncovin). See page 122 and Table 8.
vindesine A vinca alkaloid with an action similar to that of vincristine. It is used mainly in acute lyniphoblastic leukaemia in children, and in other malignant conditions not responding to treatment.
Dose: 3 nig/m` weekly by i.m. injection, subsequently increased up to 5 mg/in’ according to response. The side-effects are similar to those of other vinca alkaloids, but granulocytopenia may be a close-limiting factor. Extravasation should he avoided, as it may cause considerable local irritation. (Eldesine). See page 122 and fable R.
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vitamin D. Calciferol.
vitamin E The vitamin in the germ of wheat, rice and other grains. Deficiency States are uncommon, but may occur in cystic fibrosis and other conditions where fat absorption is impaired. It has been used empirically in many other
conditions, but its therapeutic value is questionable.
Dose: 5-15 ing daily. Now largely replaced by the synthetic form tocopherol.
vitamin K The vitamin concerned with the formation of prothrombin, and so with blood coagulation. Given as menadiol in haemorrhagic disorders, vitamin K, or phytomenadione has a similar but more rapid and sustained action. Of no value when the prothrombin level of the blood is adequate.
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vinorelbine A cytostatic drug of the vinca alkaloid type. It is used in non-small cell lung cancer and in advanced breast cancer resistant to other drugs.
Dose: 25-36 ing/inweekly by i.v.
infusion. Main side-effect is neutropenia. (Navelbine). See page 122.
vitamin A One of the vitamins obtained from fish-liver oils. A deficiency in the diet causes night-blindness, skin changes and a decreased resistance to infection. Dose: 2500-25 000 units daily.
vitamin B A group of water soluble vitamins obtained from yeast or rice polishings. The constituents include thiamine, riboflavine, nicotinic acid, pyridoxine, and small amounts of other factors.
vitamin B. Pyridoxine.
vitamin B,, Cynacobalamin. vitamin C Ascorbic acid.
warfarin A synthetic anticoagulant similar to phenindione, but with reduced side-effects and it is now the preferred drug. It is used mainly in deep-vein thrombosis and transient brain ischaernia, in doses based on the prothrombin time as
reported by the laboratory in terms of the International Normalized Ratio (INR). Dose: Pending INR report, 10 ing daily initially for up to 3 days. Haemorrhage is the main side-effect, and may require the use of phytornenadione to control the excessive response.
Whitfield’s ointment Benzoic acid 6%, salicylic acid 3%. Has keratolytic and fungicidal properties, and is used mainly for ringworm.
wool alcohols A water-in-oil emulsifying agent obtained from wool fat. It is used in many water-containing ointments, such as ointment of wool alcohols and hydrous ointment.
vitamin D The vitamin essential for the absorption of calcium and phosphorus and subsequent bone formation. Several forms of the vitamin are known, but it is used chiefly as calciferol. Vitamin D is activated in the liver and kidneys to more powerful derivatives such as calcitriol and alfacalcidol.
wool fat A pale yellow, waxy substance, also known as lanolin, obtained from sheep’s wool. It consists mainly of cholesterol-derivatives, and is a constituent of various water-in-oil emulsifying and emollient ointment bases. It may cause skin sensitization in some susceptible patients.

xamoterol A partial 0, adrenoceptor agonist with a cardiac stimulant action. It is given only in mild chronic heart failure to control exercise-induced symptoms. Dose: 400 ing daily. Side-effects are dizziness, headache and gastrointestinal disturbances. Contraindicated in severe heart failure, and care is necessary in asthmatic conditions. (Corwin). See page 141 and Table 18.
xipamide A long-acting diuretic and anti-hypertensive similar to chlorthalidone. Dose: in hypertension, 20 ing is given as a morning close: in oedematous states, 40-90 mg as a single dose, reduced later as necessary. (Diurexan). See page 148 and Table 21.
xylometazoline A sympathomimetic agent used as a nasal decongestant, and to relieve allergic conjuncfivitis as drops of 0.05-0.1%. Rebound congestion may be a side-effect.
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zalcitabineV An antiviral agent used in the suppressive treatment of AIDS patients who have become resistant to or have failed to respond to zidovudine therapy. Dose: 2.25 nig daily under expert supervision, as the drug has many side-effects including
., peripheral neuropathy. 0 livid).
zidovudine An antiviral agent effective against the human immunodeficiency virus (HIV) associated with the acquired immune deficiency syndrome (AIDS). It inhibits the enzyme reverse transcriptase and, by preventing the formation of viral DNIA, it inhibits viral development. Dose: 33 ing/kg4-hourly for some months. Side-effects include anaemia, neutropenia, nausea, fever and malaise. Liver-function tests are necessary during treatment. The chronic use of analgesics such as paracetamol may increase the risk of neutropenia. (Retrovir). See page 144 and “table 19.
zinc oxide A soft white powder widely used in dusting powders, ointments, pastes, etc., for its mild astringent and antiseptic properties. It is a constituent of Lassar’s paste, Unna’s paste, Calamine Lotion and similar preparations.
zinc sulphate Used as an astringent and stimulating lotion (1%) for indolent ulcers; and in conjunctivitis as eye drops (0.25%).
zinc undecenoate A white insoluble powder. Constituent of dusting powders and ointments for mycolic conditions.
zolmitriptan A serotonin receptor agonist used only in the treatment of acute migraine.
Dose: 2.5 ing as soon as possible after onset. .A second dose may be given not less than 2 hours later if symptoms persist. Vornig). See page 154 and Table 23.
zolpidem A mild hypnotic that acts by binding with a sub-group of benzodiazepine receptors. It has a rapid action, and is used in the short-term treatment of insomnia.
Dose: 10 mg. Side-effects are dizziness and gastrointestinal disturbance. (SI ilnoct). See page 152 and Table 22.
zopiclone A mild hypnotic that binds with a sub-group of benzodiazepine receptors, and may modulate the neurotransmitter GABA.
Dose: in insomnia and early awakening, 7.. —]S mg with initial doses of 3.75 mg for the elderly. A side-effect is a bitter or metallic after-taste. (Zimovane). See page 152.
zuclopenthixol A powerful tranquillizing drug with actions, uses and side-effects similar to those of chlorpromazine. It is of value in schizophrenia with agitation and aggression.
Dose: 20-30 mg or more up to 150 mg daily. For depot maintenance treatment, 100-200 mg or more by deep i.m. injection at intervals of 2-3 weeks, according to need and response. (Clopixol). See page 168.

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).