Not All Side Effects Associated With Tricyclic Antidepressant Therapy Are True Side Effects

Background & Aims: Patients with functional gastrointestinal disorders treated with tricyclic antidepressants sometimes report nongastrointestinal symptoms; it is unclear whether these are drug side effects or reflect a behavioral tendency to report symptoms. We evaluated whether symptoms reported before treatment with a tricyclic antidepressant (desipramine) increased in number or worsened in severity after 2 weeks of treatment and assessed the baseline factors that predispose patients to report symptoms. Methods: Female patients in a multicenter National Institutes of Health trial for functional bowel disorders completed a 15-item symptom questionnaire at baseline (before randomization), 2 weeks after they were given desipramine (n = 81) or placebo (n = 40), and at study completion (12 weeks). Patients were asked about the severity and frequency of 15 symptoms. Results were analyzed from 57 patients given desipramine who completed the questionnaires. Results: Symptoms reported as side effects to have occurred more frequently and also worsened at week 2 in the group given desipramine included dizziness, dry mouth/thirstiness, lightheadedness, jittery feelings/tremors, and flushing. Symptoms that did not change in severity or showed improvement at week 2 in the group given desipramine included morning tiredness, nausea, blurred vision, headaches, appetite reduction, and trouble sleeping. Psychologic distress but not desipramine blood level correlated with symptom reporting. Conclusions: most symptoms often attributed to side effects of desipramine were present before treatment; only a few, related to anticholinergic effects, worsened 2 weeks after treatment, suggesting that most so-called side effects were not associated specifically with desipramine use. Such symptoms might instead be associated with psychologic distress.