Uricosuric effect of irtemazole in healthy subjects.

Following a single dose of 50 mg irtemazole per os, plasma uric acid levels decreased after 1 h and fell to 53.5% of the original value within 6-12 h. Renal uric acid excretion increased up to 66 mg/h 30 min after drug application and reached its maximum of 151 mg/h 30 min later. Uric acid clearance also increased after 30 min and reached its maximum of 56 ml/min after 60 min. The response of the kidney to irtemazole is faster than to benzbromarone or probenecid. Lowering of plasma uric acid has a shorter-lasting effect than benzbromarone or probenecid. At 24 h after the application of 50 mg irtemazole the decrease of the plasma uric acid was between 15.4% and 30.0%, or 24.7% on average. Three days after the application the basic plasma uric acid levels were reached again.