Background: The efficacy of unselected monoamine reuptake inhibitors (tricyclic antidepressants) in the treatment of patients with functional gastrointestinal disorders (FGD) has not been convincingly demonstrated. We investigated the efficacy of an antidepressant (mianserin) with a different receptor profile (combined 5-hydroxytryptamine-2 + 3 and alpha-2 antagonist) in FGD.
Methods: After excluding patients with psychopathology and initial placebo responders from the study, eligible patients (n = 49) were randomized to 7 weeks of double-blind treatment with either mianserin, 120 mg/day, or placebo. Efficacy was assessed by using observer-completed ratings, the Global Improvement Scale, and patient self-ratings, Visual Analog Scale, and Disability Scales.
Results: Patients taking mianserin reported less abdominal pain, symptoms of abdominal distress, and functional disability than those given placebo (p < 0.001). The efficacy was significant across different lengths of illness periods and types of functional disorder. There was no major change 4 weeks after tapering.
Conclusion: Mianserin may be an effective and well-tolerated pharmacologic short-term treatment for functional gastrointestinal disorders in patients with no clinical evidence of psychopathology.