Chlorprothixene-induced hypouricemia: a biologic indicator of drug compliance.

Chlorprothixene is a neuroleptic as well as a potent uricosuric drug that consistently lowers the levels of plasma uric acid (PUA). The usefulness of this relative hypouricemia as an indicator of compliance with treatment was evaluated in 17 outpatients treated from 120 to 600 days. Plasma uric acid values were substantially reduced in all patients with all doses within the therapeutic range. Low levels of PUA remained stable as long as the patients were treated and returned to normal within 7 days after treatment was terminated. The authors discuss the advantages and the limitations of PUA as an indicator of chlorprothixene treatment compliance.