A significant proportion of patients with irritable bowel syndrome are also suffering from some degree of depressive disorder due to the impact of the disease on their quality of life. This study investigated the effect of anti-inflammatory drugs in the simultaneous treatment of depression and irritable bowel syndrome.

The study was performed as a double-blind randomized clinical trial. The population includes 58 patients of 18 to 60 years of age, with simultaneous irritable bowel syndrome and depression whom attended the Sanandaj healthcare centers in 2020. The population was randomly divided into two groups of intervention and control. The intervention group was treated with fluoxetine and celecoxib and the control group was treated with fluoxetine and placebo. Patients' depression scores in both intervention and control groups were measured and recorded with Beck questionnaire before treatment, three weeks and six weeks after treatment, respectively. Data were analyzed using SPSS software - version 21 - at 95% confidence level.

In the intervention and control groups, the mean age of patients was86/9±45/33 and 05/9±83/32 years (P=0.08), the proportion of women was 62.9% and 37.9% (P=0.606). Depression score of day zero was 75/6±82/20 and75/6±65/18 (P=0.241), three weeks later it was 72/5±52/9 and 75/6±10/12 (P=0.123), and finally, it was 08/5±20/7 and50/6±17/11 (P=0.011) six weeks after the treatment.

In patients with irritable bowel syndrome and concomitant depression, co-administration of fluoxetine with celecoxib in comparison with fluoxetine alone, without causing side effects within six weeks after treatment, significantly reduces the depression score.