(British Approved Name, US Adopted Name, rINN)
International Nonproprietary Names (INNs) in main languages (French, Latin, Russian, and Spanish):
Pharmacopoeias. In Europe and Japan.
European Pharmacopoeia, 6th ed., 2008 and Supplements 6.1 and 6.2 (Benzbromarone). A white or almost white crystalline powder. Practically insoluble in water; sparingly soluble in alcohol; freely soluble in acetone and in dichloromethane. Protect from light.
Benzbromarone may cause gastrointestinal adverse effects, especially diarrhoea. It may precipitate an acute attack of gout and cause uric acid renal calculi and renal colic. Hepatotoxicity has occurred and monitoring of liver function has been recommended.
Effects on the liver. Benzbromarone-induced liver damage has been reported.
Benzbromarone should be avoided in patients with moderate or severe renal impairment, in those with uric acid renal calculi, and in those with urinary uric acid excretion rates of greater than 700 mg per 24 hours. Like other uricosurics, treatment with benzbromarone should not be started during an acute attack of gout. Similarly, an adequate fluid intake should be maintained to reduce the risk of uric acid renal calculi; additionally, alkalinisation of the urine may be considered.
Porphyria. Benzbromarone is considered to be unsafe in patients with porphyria because it has been shown to be porphyrin-ogenic in in-vitro systems.
Aspirin and other salicylates antagonise the effect of benzbromarone. Benzbromarone may increase the anticoagulant activity of coumarin oral anticoagulants (see under Interactions of Warfarin).
Antigout drugs. For mention of the effects of benzbromarone on the clearance of oxipurinol, the major active metabolite of allopurinol, and the view that this was not clinically significant, see under Interactions of Allopurinol.
Benzbromarone is only partially absorbed from the gastrointestinal tract, reaching peak plasma concentrations about 2 to 4 hours after an oral dose. Benzbromarone is extensively bound to plasma proteins. It is metabolised in the liver, and is excreted mainly in the faeces; a small amount appears in the urine.
Uses and Administration
Benzbromarone is a uricosuric drug that reduces plasma concentrations of uric acid by blocking renal tubular reabsorption. It has been suggested that benzbromarone may also increase the intestinal elimination of uric acid. It has been used to treat hyperuricaemia including that associated with chronic gout although it has been withdrawn in many countries due to reports of hepatotoxicity.
Benzbromarone is not used to treat acute attacks of gout and may exacerbate and prolong them if given during an attack; treatment should not start therefore until an acute attack has subsided.
The usual oral dose has been 50 to 200 mg daily. An NSAID or colchicine should be given initially to reduce the risk of precipitating acute gout. An adequate fluid intake should be maintained. Lower doses of benzbromarone (20 mg) have also been used in the form of a combination product with allopurinol.
The symbol ¤ denotes a preparation which is discontinued or no longer actively marketed.
Argentina: Max Uric¤; Austria: Uricovac; Belgium: Desuric¤; Brazil: Narcaricina; France: Desuric¤; Germany: Azubromaron¤; Harolan¤; Narcaricin¤; Uricovac¤; Hong Kong: Narcaricin¤; Hungary: Harpagin; Japan: Urinorm; Malaysia: Harpagin¤; Mexico: Desuric¤; Netherlands: Desuric; South Africa: Minuric¤; Singapore: Narcaricin¤; Spain: Urinorm; Switzerland: Desuric¤; Obaron¤; Thailand: Narcaricin;
Austria: Allobenz; Duovitan¤; Gichtex plus; Uroplus¤; Belgium: Comburic; France: Anurate¤; Desatura¤; Germany: Acifugan¤; Allo.comp.; Allomaron¤; Harpagin; Uricovac comp¤; Italy: Urifugan¤; Portugal: Acifugan¤; South Africa: Allomaron; Spain: Acifugan¤; Facilit¤; Switzerland: Acifugan¤; Thailand: Allomaron