Uricosuric effect of irtemazole in hyperuricemic patients without and with renal insufficiency.

A single oral dose of 50 mg irtemazole exhibited a clear cut uricosuric effect in five patients with hyperuricemia and normal renal function. The average maximal decrease of plasma uric acid was 46.1% compared to the initial value; it was reached between 6 h and 12 h after drug administration. Extent and course of plasma uric acid showed no differences between normouricemic (5) and hyperuricemic subjects. In four patients suffering from hyperuricemia and renal insufficiency only a minor effect of irtemazole was seen. The average maximal decrease of plasma uric acid reached 12.8% compared to the initial value. It occurred between 8 h and 12 h after drug ingestion. In both normouricemic and hyperuricemic subjects irtemazole acts more quickly than benzbromarone and probenecid. The duration of its uricosuric effect is shorter. Like benzbromarone, irtemazole exhibits only a minor effect in patients with reduced creatinine clearance.