Selective Serotonin Re-uptake Inhibitors (SSRIs)

How it works: Acts on serotonin levels in nerves within the gastrointestinal tract, spinal cord, and brain to improve abdominal and bowel symptoms.

Which symptoms does it help: Overall IBS symptoms. They accelerate GI transit and therefore may improve symptoms of constipation as well.

How long it takes to see a benefit: 2-4 weeks.

FDA approved: N/A

Dosage: The dose varies between SSRIs.

Special considerations or risks: Serotonin syndrome could happen as the result of drug interactions with monoamine oxidase inhibitor medications. Abrupt discontinuation of SSRIs may precipitate dizziness, gastrointestinal distress, fatigue, chills, and body ache.

Most common side effects: Insomnia, drowsiness, dry mouth, sexual dysfunction, and weight gain.

Recommendation: ACG suggests SSRIs for overall symptom improvement in IBS patients. (Recommendation: weak; Quality of evidence: low)