In order to investigate the influence of the route of administration on behavioural effects induced by apomorphine (APO), 6 increasing doses were administered by intraperitoneal and by subcutaneous route to male Wistar rats. Dose-response curves for stereotypy, rearing, sedation, grooming, yawning and penile erection were calculated. The occurrence of stereotypy precluded other behavioural manifestations. APO was more potent when administered subcutaneously, with potency ratios between the routes of 10.4 for stereotypy, 4.6 for sedation, 6.8 for grooming, 11.8 for yawning and 7.5 for penile erection.