Abstract
The effects of haloperidol on aggressive behaviour 24 hours after administration have been studied previously with contradictory results. This study is an attempt to determine the persistence of the antiaggressive and motor effects of 0.4 mg/kg of haloperidol over time, studying its actions on agonistic behavior in male mice at 30 minutes, at 24 and at 48 hours after administration. When the test is performed 30 minutes after administration, there is a significant decrease of time allocated to offensive behaviors and nonsocial exploration and a significant increase in time devoted to immobility behavior in the animals that received haloperidol with respect to their controls. No significant effects were found 24 or 48 hours after administration. Differences with similar studies are commented upon.