Abstract
Background: Millions of people are affected by chronic pain across the globe, which is commonly associated with depression. Fluoxetine, an antidepressant has shown potential for analgesic effect without serious adverse effects of traditional analgesics. Hence, the current study was undertaken to evaluate the antinociceptive effect of fluoxetine.

Aim and Objective: The aim of the study was to evaluate antinociceptive activity of fluoxetine and to compare it with diclofenac.

Materials and Methods: In this study, rats of adult albino strain with weight in the range of 150–200 g were utilized. Acetic acid-induced writhing method was the screening method used. The animals were allotted to three study groups. In each of these study groups, there were five rats. Group one was injected distilled water, group two was injected with fluoxetine, and group three was injected with diclofenac. The medications, for all groups under study, were injected intraperitoneally, 30 min before the injection of acetic acid. The statistical test of significance was analysed by applying one-way analysis of variance followed up by Tukey–Kramer test.

Results: Mean ± SEM for number of writhes for different groups were as follows: Control group was 39.2 ± 1.35, fluoxetine was 37 ± 1.18, and diclofenac was 29.2 ± 1.02. After Tukey–Kramer test, P values obtained were as follow: Control with diclofenac was <0.001 and control with fluoxetine was >0.05.

Conclusions: Fluoxetine failed to show statistically significant reduction in number of writhes. This finding needs to be confirmed with large scale studies.

Key words: Antinociception; Acetic Acid-induced Writhing Method; Fluoxetine