AbstractA specific, sensitive, rapid, and reproducible method for iprindole in human plasma was developed using gas chromatography with trimipramine as internal standard. The sensitivity of the method is of S ng ml−1and a linearity was obtained for concentrations ranging from 12.5ngml−1to 100ngml−1with a regression coefficient of 0.9872. The plasma levels of iprindole were determined in five healthy volunteers following the administration of a single oral dose of 60 mg and in four patients admitted for endogenous depression after a 3‐week administration of 90mgd−1. Following a single oral dose to healthy volunteers, the maximum concentrations occurred between 2 and 4h after administration of the drug and the mean half‐life value was 52.5 h. In patients the steady‐state concentrations of iprindole ranged between 18