The electrochemical behavior of risperidone was studied in pH 7.07～10.32 B-R buffer solutions and 0.2 mol•L^－1 NaOH solution by means of cyclic voltammetry, linear sweep voltammetry, normal pulse voltammetry and controlled-potential electrolysis. Risperidone yielded one wave P₁ as pH of B-R buffer solution was changed from 7.07 up to 10.07, which was a catalytic hydrogen wave. Additional two waves P₂ and P₃ were exhibited in pH＝10.32 B-R buffer solution. P₂ wave was an irreversible adsorption reduction wave involving one electron. P₃ could be split into P_3a and P_3b. Of them, P_3a was the further reduction wave of P₂, and P_3b was a catalytic hydrogen wave. Otherwise, based on the linear relation between the first-order derivative peak current of P₁ and the concentration of risperidone in the range of 1.6×10^－5～2.0×10^－6 mol•L^－1 with a 0.995 correlation coefficient, a new method for determination of risperidone in risperidone tablets was described. The detection limit was 1.0×10^－6 mol•L^－1, and the recovery of risperidone was between 105% and 102% with a relative standard deviation of 0.84%.

Key words: risperidone, drug analysis, mercury electrode, voltammetry