Treatment of functional dyspepsia with a fixed peppermint oil and caraway oil combination preparation as compared to cisapride - A multicenter, reference-controlled double-blind equivalence study

The therapeutic equivalence of a fixed combination preparation consisting o f peppermint oil and caraway oil (PCC, Enteroplant(R)) and the prokinetic a gent cisapride (CIS, CAS 81098-60-4) was investigated in a four-week random ized controlled double-blind study with planned adaptive interim analysis. The study comprised 120 outpatients with functional dyspepsia. The efficacy was evaluated in 118 patients. Of these, 60 patients received the enteric- coated combination preparation (2 x 1 capsule containing 90 mg peppermint o il + 50 mg caraway oil per day) and 58 patients received the reference prep aration cisapride (3 x 10 mg/day). The mean reduction of the pain score (primary variable) recorded on a visua l analog scale (VAS) during the four-week treatment was 4.62 points with th e peppermint oil/caraway oil preparation. This score was comparable with th e mean reduction under cisapride (4.60 points) (p = 0.021; test for equival ence). Equivalence was also found in the secondary variable "frequency of pain" wi th a reduction by 4.65 points under PCC and by 4.16 points under cisapride carried out on an exploratory basis (p = 0.0034). Comparable results were a ttained with both treatments in the Dyspeptic Discomfort Score which includ ed the other dyspeptic symptoms as well as intestinal and extraintestinal a utonomic symptoms, in the prognosis as appraised by the physician and in th e CGI scales (Clinical Global Impressions). Corresponding results were also found in Helicobacter pylori-positive patients and patients with initially intense epigastric pain in the two treatment groups. The combination preparation consisting of peppermint oil and caraway oil ap pears to be comparable with cisapride and provides an effective means for t reatment of functional dyspepsia. Both medications were tolerated well (adv erse events were reported in 12 patients of the PCC group and in 14 patient s of the CIS group).