Efficacy and tolerability of a fixed combination of peppermint oil and caraway oil in patients suffering from functional dyspepsia

Aim: To assess the efficacy and safety of enteric coated capsules containing a fixed combination of 90 mg peppermint oil and 50 mg caraway oil (PCC; Enteroplant) in patients with functional dyspepsia. Methods: A total of 96 out-patients received one capsule twice daily of PCC or placebo for 28 days. Primary efficacy variables were the intra-individual change in (i) pain intensity and (ii) sensation of pressure, heaviness and fullness between days 1 and 29, and the investigators' rating of (iii) global improvement (Clinical Global Impressions [CGI] item 2) on day 29. A global type I error of alpha =0.05 was controlled by a priori ordering of hypotheses. Results: All patients were evaluable for efficacy and safety. On day 29, the average intensity of pain was reduced by 40% vs. baseline in the PCC group and by 22% in the placebo group. With regards to pressure, heaviness and fullness, a 43% reduction was observed for PCC vs. 22% for placebo. In CGI item 2, 67% (PCC) vs. 21% (placebo) of the patients were described as much or very much improved. In all three target parameters, the superiority of PCC over placebo was statistically significant. Six patients (PCC: 5; placebo: 1) reported adverse events, either unrelated to the trial, or attributable to an aggravation of the disease under investigation. Eructation with peppermint taste did not occur. Conclusion: These results demonstrate the good tolerability and the favourable risk-benefit ratio of PCC for the treatment of functional dyspepsia.