A-Z Principal Drugs (potassium permanganate - proxymetacaine)
potassium permanganate Purple crystals, soluble in water. A powerful oxidizing and deodorizing agent used 1:1000 as lotion, 1:10000 to 1:5000 as mouthwash, douche, bladder washout and bath.
povidone-iodine A complex of iodine with an organic carrier. When applied to the skin it slowly releases iodine, and has an extended antiseptic action. Used for local application to the skin and mucous membranes as solution containing the equivalent of 0.75-1 % of iodine.
pralidoxime A reactivator of cholinesterase. Organophosphorus insecticides inhibit that enzyme, and poisoning by such insecticides is an occupational hazard. Their toxicity can be reversed in part by the injection of 2 mg atropine, but the enzyme can be reactivated and muscle power restored by pralidoxime (30 mglkg) given by slow i.v. injection, repeated as required. It is effective only if given within 24 hours of exposure to the insecticide.
pravastatin A blood lipid-lowering agent with the specific enzyme-inhibiting properties of simvastatin, and used in primary hypercholesterolaemia not responding to the other drugs.
Dose: 10 -40 mg daily as a single dose. Side-effects include myalgia, rash and gastrointestinal disturbances. (Lipostat). See page 146 and Table 20.
prazinquantel A schistosomicide of low toxicity, effective against Schistosonia hamratobium, S, mansoni and S. japonicum It is also active against tapeworm. Dose: 10-20nig/kg as a single oral dose. (Biltricide).
prazosin An alpha-adrenoceptor blocking agent and vasodilator used in the treatment of hypertension and congestive heart failure.
Dose: I mg daily initially, increased as required up to a maximum of 20 mg daily. The initial dose may cause marked hypotension, and it should be taken at night, in bed. prazosin is also given in benign prostatic hypertrophy in maintenance doses of 4 mg daily. Side-effects are drowsiness, nausea and postural hypotension. (Hypovase). See page 148 and Table 21.
prednisolone A glucocorticosteroid with the actions and uses of hydrocortisone, but effective in much lower doses. It is often the preferred drug for oral use, and is given in a wide range of conditions including asthma, severe allergic reactions, rheumatoid arthritis, collagen disorders and inflammatory skin conditions. prednisolone is also of value in leukaemia, ulcerative colitis, the nephrotic syndrome, pemphigus, sarcoidosis, myasthenia gravis, haemolytic anaemia, agranulocytosis and other blood dyscrasias. Large doses are given in the immunosuppressive control of transplant surgery. The dose varies with the nature and severity of the condition being treated, and in every case the lowest dose required to evoke an adequate response should be used, after which the dose should be reduced in stages. Dose: in rheumatoid arthritis, 7.5-10 ing daily initially; other conditions may require doses up to 100 mg daily. Dose by i.m. injection 25-100 ing once or twice a week. Asa retention enema, 20 mg to relieve the inflammation of colitis and Crohn’s disease; as eye drops and ear drops, 0.5% solution. The side-effects are those of the corticosteroids generally, and include salt and water retention, hypertension, muscle weakness and peptic ulcer.
prednisone A glucocorticosteroid that is converted to prednisolone in the body, and so has the actions and uses of that drug.
prilocaine A local anaesthetic with the actions, uses and side-effects of lignocaine. (Citanest).
primaquine An antimalarial drug used mainly to prevent a relapse of benign tertian malaria after treatment with chloroquine, as it kills the malarial parasites that may still be present in the liver. Dose: 13 mg daily, for 2-3 weeks after chloroquine treatment. Side-effects are nausea and abdominal pain.
primidone An anticonvulsant used in the treatment of grand mat and psychomotor epilepsy.
Dose: 125nig daily initially, slowly increased as required up to a maximum of 1.5 g daily. Side-effects include drowsiness, nausea, blurred vision and rash. (Mysoline). See page 136 and Table 15.
probenecid A uricosuric agent that
increases the excretion of uric acid, and so is useful in the treatment of gout and hv
I peruncacrina.
Dose: O.5-2 g daily. An adequate fluid intake and an alkaline urine are necessary for the best response. probenecid also delays the excretion of penicillin and sonic cephalosporins, and is given in doses of 2 g daily to raise the plasma level of those antibiotics. Side-effects include occasional nausea, flushing and dizziness. (Benernid). ,See page 140 and Table 17.
procainamide A procaine derivative occasionally of value in the treatment of ventricular arrhythmias.
Dose: till to 50 mg/kg daily. It is also given by slow i.v. injection under E’C.C, control in doses of 25-50 ing/tininute up to a maximum of I g. Side-effects are gastrointestinal disturbances, lever and rash. (Prones(vi).
severe nausea and vomiting, 20 mg orally, or 12.5 mg by deep i.m. injection. It is also used as suppositories of 25 ing. (Stemetil). See page 168 and Table 30.
procyclidine An anticholinergic drug similar to benzhexol, used mainly in the treatment of parkinsonism. Reduces rigidity more than tremor.
Dose: 73-30 mg daily. In acute states it is given by i.m. injection in (loses of-i-10 mg, or 5 mg doses i.v. (Arpicolin; Kernadrin). See page 160 and Table 26.
progesterone The hormone of the corpus luicum, responsible for the preparation of the uterus to receive a fertilized ovum. It is used in dysfunctional uterine bleeding and in the premenstrual syndrome. Dose: 200-400 nig daily per ragina on a cyclic basis. (Cyclogest). Also a constituent of sonic oral contraceptives. See dydrogesteronc and norethisterone.
proguanil hydrochloride A synthetic antimalarial of high potency and low toxicity, used in the prophylaxis and suppressive treatment of malaria, often in association with chloroquine.
Dose: 100-200 rig daily, and continued for 6 weeks after leaving the infected area. (PaILICIrinc).
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procaine A local anaesthetic now largely replaced by lignocaine.
procaine penicillin An old long-acting loan of penicillin, given together with penicillin G to obtain a high initial blood level. It is now used mainly in early syphilis. Dose: 900 mg daily by Lin. injection for 10 days. (Ificillin).
procarbazine A cytotoxic drug used mainly as part of a multi-drug treatment of Hodgkin’s disease. It is also used to treat other lymphomas no longer responding to other therapy.
Dose: 50 ing initially, increasing to a maxiintini of 300 mg daily. Side-effects include nausea, anorexia and bone marrow depression. Alcohol may cause a disulfiram reaction. (Nitulan). See page 122 and Table 8.
prochlorperazine A tranquillizer with the actions, uses and side-effects of chlorpromazine.
Dose: in schizophrenia, 25-100 Tng daily; in severe anxiety, 15-20 mg daily. In
promazine A tranquillizer with the actions, uses and side-effects of chlorpromazine, but less potent. It is used mainly to
control agitation in the elderly, and in other minor conditions of psychiatric disturbance.
Dose: 50-800 ing daily, adjusted to need .111d response; by injection 25-50 mg. (Sparine).
promethazine A long-acting antihistamine with sedative properties. It is used for the relief of a wide range of allergic conditions, in mild insomnia and for preoperative sedation. It is also of value as an antiemetic in the prophylaxis and treatment of travel sickness, vertigo and drug-induced nausea.
Dose: 25-50 mg daily; 25-100 ing by deep i.m. injection. In anaphylaxis, sometimes given by slow i.v. injection in doses up to 100 mg to supplement previously injected adrenaline. The side-effects are those of the antihistamines generally. (Phenergan). See page 110 and Table 2.
propafenone An anti-arrhythmic agent of the lignocaine type, used in the prophylaxis and treatment ofventricular arrhythmias. Dose: under ECG control 450 ing daily initially, after food, increased at 3-day intervals up to a maximum of 900 mg daily. Side-effects are dizziness, gastrointestinal disturbances and postural hypotension. (Arythniol).
propantheline An anticholinergic agent used as a spasmolytic in gastrointestinal disorders, in urinary frequency associated with bladder neck weakness, and in nocturnal enuresis.
Dose: 45-120 mg daily at least I hour before food. Side-effects include dryness of the mouth and blurred vision. (Pro- Banthine). See page 174 and Table 33.
propofol A non-irritant short-acting i.v. anaesthetic for smooth induction and maintenance of general anaesthesia for up to I hour. Dose: 2-2.5 mgft initially, followed by Supplementary doses of 0.1-0.2
ing/kg1min as required but some local pain may occur. Side-effects include mild hypotension, transient apnoea an([ bradycardia. Recovery is normally rapid and uneventful but delayed recovery, convulsions and anaphylaxis have been reported. Care is necessary in cardiovascular, respiratory or renal impairment. (Diprivan).
propranolol A beta-adrenoceptor blocking agent that reduces the cardiac response to circulating adrenaline and noracircrialine. It reduces the load on the heart during
exercise and stress, and is used in the treatment of angina, coronary insufficiency, cardiac arrhythmias, hypertension, and after myocardial infarction. It also ameliorates the tremor and palpitation of transient anxiety and stress, and is useful ill the prophylactic treatment of migraine. Dose: 160-320 mg daily according to need. In arrhythmias and thyrotoxic crisis, propranolol is given by slow i.v. injection in doses of I ing, repeated up to a maximum of 10 ing. Side-effects are bradycardia, bronchospasni and gastrointestinal disturbances. Care is necessary in renal and hepatic deficiency, asthma is a contraindication. (Inderal). See page 146 and’I'able 21.
propylthiouracil A thyroid inhibitor occasionally used as an alternative to carbiniazole in hyperthyroidism. Dose: 300-450 ing daily.
prostacyclin See epoprostenol.
prostaglandin A generic term applied to a series of closely related hormone-like fatty acid derivatives, originally extracted front the prostate gland, but now prepared
synthetically. Prostaglandins are widely distributed in animal tissues, and have a complex and varying range of biological activity.’rhus they may have a smooth muscle stimulating or relaxant action, pressor, vasodilator, inflammatory or other properties. The anti-inflammatory action of aspirin and related drugs is due to an inhibition of prostaglandin synthesis. See alprostadil, carboprost, dinoprostone and genieprost.
protamine sulphate A simple protein obtained from fish sperm. It neutralizes the anticoagulant effect of heparin, and it is used in controlling the haemorrhage i hat may occur during heparin therapy. Dose: 1% solution i.v. according to need; ling will neutralize 80-100 units of heparin.
prothionamide A second-line antitubercular drug that has been used in resistant tuberculosis. See page 170 and Table 31. It has also been used in the treatment of leprosy.
protirelin The thyrotrophin- releasing hormone (TRH) of the hypothalamus. Dose: in the diagnosis of hyperthyroidism, as a single i.v. dose ol’200 pg. It normally induces a rapid rise in the plasma levels of thyrotrophin, but in thyrotoxicosis that rise does not occur. Side-effects include nausea, flushing, a strange taste and urinary urgency.
protriptyline A tricyclic antidepressant with actions and uses similar to amitriptyline. It is used in depression associated with apathy, as it has some stimulant action. Dose: 15-40 mg daily. Side-effects are cardiovascular distu&nce, rash and photosensitivity. (Concordia). See
page 128 and Table 11.
proxymetacaine A local anaesthetic used as 0.5% drops in ophthalmology. (Oplithaine).
pseudoephedrine A drug very closely related to ephedrine, but now used mainly as a respiratory decongestant. It has been used in nocturnal enuresis, but may cause hallucinations in sonic children.

