Sulfinpyrazone1 has long been recognised as a potent uricosuric agent, but has more recently been studied extensively as a platelet inhibitor and antithrombotic agent. It is active in man following oral administration and has been reported to be effective in reducing the incidence of transient ischaemic attacks, thromboembolism associated with vascular and cardiac prostheses, recurrent venous thrombosis, arteriovenous shunt thrombosis and sudden cardiac death following myocardial infarcton. Sulfinpyrazone has not been demonstrated to be effective in preventing or reducing the risk of stroke or death in patients with cerebrovascular disease with a recent history of cerebral or retinal ischaemioc attacks. The normal total dose of sulfinpyrazone as an antithrombotic agent is 800mg daily. The drug has been used continuously for up to 4 years with no serious adverse reactions or laboratory abnormalities. There has been no apparent diminution of effect with time. Sulfinpyrazone is not a substitute for conventional anticoagulant agents (e.g. the coumarin derivatives) in the treatment of venous thrombosis, but is an important drug for the treatment of conditions associated with arterial thrombosis and possibly for the prophylaxis of recurrent venous thrombosis.