Toxic effects of psychotropics related to possible p450 enzyme inhibition by kava: report of 2 cases.

Kava is an herbal remedy popular for centuries among native Pacific Islanders for its sedative effects and use in religious ceremonies. Kava gained popularity in Western countries due to its anxiolytic properties; however, very little is known about potential adverse reactions to kava other than reports of hepatotoxicity. Two cases of patients seen on the psychiatric emergency and consult service who developed severe side effects from psychotropic medications in the context of kava use are presented. In both cases, kava use may have affected the metabolism of the psychotropic medications, leading to serious side effects. Growing research indicates that kava most likely alters concentrations of coadministered psychotropics possibly by inhibiting cytochrome P450 enzymes. This case series highlights the need for greater awareness of safety issues among kava users who also take medications that, when combined with kava, can be life-threatening at toxic levels. Pharmacogenomic testing along with further research about kava and its metabolites could help determine a pharmacologic solution for patients who require psychotropic medications but who would like to preserve cultural traditions and religious practices.