The electrochemical reduction of pivazepam was investigated by differential pulse polarography. Keduction of the drug was carried out in one irreversible, diffusion-controlled step using Britton-Robinson buffers. The peak potential at pH 5.0 and 10% methanol-water solutions was -0.95 V (vs. Ag/AgC1/3M KCI). Pivazepam can be determined (c1ou.n to the nanomolar level) by using adsorptive preconcentration prior to the differential pulse voltammetric scan. The applicability to assays of commercial preparations and human urine is described. The detection limit was 15 ng per milliliter o f urine with 60 seconds adsorption, and the mean standard deviation was lower than 4.6% for 200 ng/mL sample ( n = 5, 60 seconds), with a mean recovery o f 82%.