Pharmacokinetics of acitretin.

Acitretin, the metabolite of etretinate, is eliminated far more rapidly from the human body than is etretinate. It has therefore been suggested that only a short period of contraception would be required following the completion of long-term therapy. However, recent studies have demonstrated the presence of etretinate in the plasma of acitretin-treated patients. In this paper, we review the results of studies at our centre in view of the recently discovered metabolic pathways for acitretin. Re-esterification of acitretin to etretinate, however, results in a loss of the metabolic advantages of acitretin. Because of this new knowledge, the recommended contraception period after acitretin therapy has been lengthened to 2 years.