Comparison of the potency of nortriptyline and mirtazapine on gastrointestinal symptoms, the level of anxiety and depression in patients with functional dyspepsia

In the current clinical trial study, the potency of mirtazapine and nortriptyline was compared in patients with Functional Dyspepsia (FD) who had anxiety or depression.

FD usually accompanies other psychosocial disorders. According to previous studies, among these disorders, anxiety and depression have the most correlation.

This randomized clinical trial was organized in Taleghani hospital (Tehran, Iran). In two parallel groups, 42 patients were treated for 12 weeks, with 22 patients receiving 7.5 mg of mirtazapine and 20 patients receiving 25 mg of nortriptyline per day. To gain robust results, the patients with a positive history of antidepressant therapy, organic diseases, alcohol abuse, pregnancy, and major psychiatric disorders were excluded from the study. The subjects were examined by three questionnaires, including Nepean and Hamilton questionnaires. The patients were asked to answer the questions three times during the study: once before the onset of the treatment,  second during the treatment, and third at the end of the treatment.

 Based on Gastrointestinal (GI) manifestations, mirtazapine, in comparison to nortriptyline could significantly suppress the signs and symptoms of FD, including epigastric pains (P=0.02), belching (P=0.004), and bloating (P=0.01). Although the results from the use of mirtazapine compared to the use of nortriptyline (P=0.002) showed a lower mean depression score on the Hamilton questionnaire, no significant differences were found between the effects of these drugs on the anxiety scale of patients (P=0.091).

Mirtazapine is more effective for GI symptoms related to gastric emptying. Considering the level of anxiety, mirtazapine, compared to nortriptyline, revealed better outcomes in FD patients suffering from depression.