Evaluation of antidepressant activity of tramadol in mice

Objective: To evaluate antidepressant like effect of tramadol in mice.
Materials and Methods: Tramadol was administered at three different doses (10,20 and 40 mg/kg,i.p) once daily for 7 days to Swiss albino mice of either sex. The immobility period of control and drug treated mice were recorded in tail suspension test (TST).The antidepressant effect of tramadol was compared to that of fluoxetine (20 mg/kg, i.p), administered for seven days.
Results: Tramadol produced significant antidepressant effect at all the doses, as indicated by reduction in immobility times as compared to control. The efficacy of tramadol at doses of 20 and 40 mg/kg was comparable with that of fluoxetine. Tramadol at 10 mg/kg dose showed significantly less antidepressant activity compared to fluoxetine.
Conclusion: The results of the present study indicate antidepressant like activity of tramadol.