What is the role of loperamide in IBS?
- Loperamide is a synthetic peripheral opioid agonist that reduces gut transit. By binding to the μ opioid receptors on the myenteric neurons in the upper and lower bowel, loperamide reduces gut motility, which allows for greater fluid absorption and improved stool consistency.
- Loperamide does not cross the blood-brain barrier at standard doses, and therefore does not have central nervous system side effects, such as sedation or addiction.
- Most patients with IBS experience reduction in diarrhea and frequency, as well as improvement in stool consistency.
- Loperamide 2 to 4 mg each morning after the initial bowel movement and before social events can reduce undesirable urges to defecate, and increases confidence and willingness to engage in social activities.
