Irritable bowel syndrome is commonly treated with which class of medication?

• A. Selective serotonin reuptake inhibitors (SSRI)
• B. Monoamine oxidase inhibitors (MAOI)
• C. Tricyclic antidepressants (TCA)
• D. Antihistamines

Answer: (A)

Antidepressants are used in irritable bowel syndrome to modulate the gut–brain axis and reduce visceral hypersensitivity, helping with abdominal pain and abnormal bowel habits when lifestyle adjustments alone aren’t enough. Among the antidepressant options, low-dose tricyclic antidepressants are the most supported for IBS because their anticholinergic effects slow intestinal transit and blunt pain signals from the gut. This combination often translates into less cramping and fewer bowel movements for patients with diarrhea-predominant IBS, and they can also help patients who have concurrent mood symptoms. If a patient has significant anxiety or depressive symptoms, an SSRI might be considered, but SSRIs are not the primary choice for addressing IBS pain and stool symptoms themselves. Monoamine oxidase inhibitors aren’t used for IBS due to safety concerns and limited evidence in this context, and antihistamines don’t target the underlying gut–brain dysregulation seen in IBS.