The efficacy and safety of hyoscyamine, dicyclomine, and desipramine in the treatment of irritable pouch syndrome-a retrospective cohort study.

Abstract

Background: Patients with ileal pouch-anal anastomosis (IPAA) frequently experience high bowel frequency and abdominal pain that are disproportionate to endoscopic inflammation, a condition often termed irritable pouch syndrome. Although antispasmodic agents and neuromodulators are widely used in irritable bowel syndrome, real-world data supporting their effectiveness and durability in patients with pouches remain limited.

Methods: We performed a retrospective cohort study of IPAA patients followed at a pouch clinic between 2014 and 2025. Patients treated with hyoscyamine extended release (ER), dicyclomine, or desipramine for high bowel frequency or abdominal pain were included. Patients could receive multiple therapies sequentially over time. Clinical response was determined by physician-documented symptom improvement. Treatment persistence was assessed using electronic medical record prescription data.

Results: Among 219 eligible patients, 329 treatment courses were analyzed: 143 hyoscyamine ER, 80 dicyclomine, and 106 desipramine. In patients with high bowel frequency, 235 treatment courses resulted in clinical improvement in 68.5% of patients receiving hyoscyamine ER, 65.0% of those receiving dicyclomine, and 63.5% of those receiving desipramine. For abdominal pain (94 treatment courses), improvement for hyoscyamine ER, dicyclomine, and desipramine was observed in 61.5%, 68.3%, and 76.2% of courses, respectively. Approximately 60% of treatment courses persisted beyond one year. Long-term persistence (≥3 years) was highest with dicyclomine (48.7%), followed by desipramine (38.7%) and hyoscyamine ER (37.8%). Adverse events were infrequent and consistent with known safety profiles.

Conclusions: Antispasmodic agents and low-dose neuromodulators are associated with meaningful symptom improvement in patients with irritable pouch syndrome, supporting their role as adjunctive therapies for pouch-related functional symptoms.