ABSTRACT
Background: Pain is an unpleasant sensation with varying subjective experience. Its management is always challenging for physicians particularly in case of chronic pain. Chronic pain and depression usually co-exist due to poor quality of life and increase in health care costs posing an individual to suffer from depression. Anti-depressants for pain management are being used successfully using since years. In this study venlafaxine, a newer anti-depressant drug was evaluated for anti-nociceptive activity, tail immersion test an analgesic animal model of albino mice.Methods: Randomly selected albino mice of either sex with reaction time of <6 seconds were included in the study and divided into 7 groups with 6 mice in each group. Grouping was done based on the drug received i.e., venlafaxine 15, 30 and 60 mg/kg, tramadol 10 and 20 mg/kg, control group (normal saline) and combination group venlafaxine 15 mg/kg+tramadol 10 mg/kg. Drugs were administered by intra-peritoneal route.Results: Venlafaxine (30 and 60 mg/kg), tramadol (20 mg/kg) and combination group venlafaxine (15 mg/kg+tramadol 10 mg/kg) has shown significant (p<0.001) increase in tail withdrawal latency compared to control group (normal saline) by tail immersion test. Venlafaxine potentiated anti-nociceptive activity of tramadol on concomitant administration with tramadol. Venlafaxine at 60 mg/kg has comparable anti-nociceptive effect to tramadol at 20 mg/kg.Conclusions: Venlafaxine at doses of 30 and 60 mg/kg is having anti-nociceptive effect, but less potent than tramadol.