Stobadine, (-)-cis-2,8-dimethyl-2,3,4,4a,5,9b-hexahydro-1H-pyrido[4;3b]-indole, is a pyridoindole derivative with antioxidant, antiarrhytmic, neuroprotective, local anesthetic, a-adrenolytic, antihistaminic, myorelaxant and other pharmacodynamic effects. The antioxidant properties were tested in a model system of egg yolk phosphatidylcholine (EYPC) multilamellar liposomes. The lipoperoxidation was induced by adding Cu2+ ions and tert-butylhydroperoxide. The course of EYPC peroxidation was monitored spectrophotometrically for conjugated diene formation. We found that stobadine prolonged the lag phase and decreased the rate of peroxidation during the lag phase in a dose-dependent manner. Surprisingly, an increase in the rate of peroxidation was observed at low stobadine concentration in the propagation phase. The possible cause of prooxidative action of stobadine is discussed.