Composition
Tab 100 mg/300 mg: Allopurinol 100 mg/300 mg.
Indications & Dosage
Prophylaxis of gout and of uric acid and calcium oxalate renal stones, Prophylaxis of hyperuricaemia associated with cancer chemotherapy: Adult: Initially 100-200 mg daily to be taken preferably after food, for maintenance adjust dose according to plasma or urinary uric acid concentration; in moderately severe conditions: Adult: 300-600 mg daily in divided doses (max. per dose 300 mg); in severe conditions: Adult: 700-900 mg daily in divided doses (max. per dose 300 mg). Dose to be taken preferably after food. Children 1 month-15 yr: 10-20 mg/kg daily (max 400 mg daily), preferably after food; 15-18 yr, initially 100 mg daily, increased according to response, max 900 mg daily (doses over 300 mg daily given in divided doses); preferably after food.
Contraindications
Not a treatment for acute gout but continue if attack develops when already receiving allopurinol, and treat attack separately
Precautions
Elderly, renal or hepatic impairment, ensure adequate fluid intake (2-3 litres/day), for hyperuricaemia associated with cancer therapy, allopurinol treatment should be started before cancer therapy. Administer prophylactic NSAID (not aspirin or salicylates) or colchicine until at least 1 month after hyperuricaemia corrected (for first 3 months) to avoid precipitating an acute attack.
Interactions
Anticoagulants, chlorpropamide, mercaptopurine or azathioprine.
Pregnancy
Caution advised, use only if no safer alternative
Lactation
Caution advised or effect undetermined.
Side Effects
GI disorders, rashes (withdraw therapy; if occur). Rare: Alopecia, aplastic anaemia, arthralgia, blood disorders, drowsiness, eosinophilia resembling Stevens-Johnson syndrome, eosinophilia resembling toxic epidermal necrolysis, exfoliation, fever, gynaecomastia, haemolytic anaemia, headache, hepatitis, hepatotoxicity, hypersensitivity reactions, hypertension, leucopenia, lymphadenopathy, malaise, neuropathy, paraesthesia, renal impairment, taste disturbances, thrombocytopenia, vasculitis, vertigo, visual disturbances