Efficacy of Mentha pulegium extract in the treatment of functional dyspepsia: A randomized double-blind placebo-controlled clinical trial

Ethnopharmacological evidence: Mentha pulegium L. leaves are used in the Iranian traditional medicine for the treatment of functional dyspepsia. Aim of study: To study the efficacy and safety of M. pulegium in the treatment of functional dyspepsia patients fulfilling the Rome III criteria. Materials and methods: The efficacy and safety of a standardized Mentha pulegium leaf extract (drug extract ratio: 15.9:1, extraction solvent: 70% v/v aqueous ethanol) (330 mg three times daily taken for 2 months) as add-on to one famotidine 40 mg tablet per day in the treatment of 50 functional dyspepsia patients were compared with those of a parallel placebo group (n =50). Results: The extract significantly decreased the total dyspepsia score measured by the Hong Kong dyspepsia index compared to the placebo and baseline (P=0.011 and P < 0.001 respectively). The stomach pain, upper abdominal bloating, upper abdominal dull ache, belching and total dyspepsia scores were decreased from baseline in the extract group significantly compared to the placebo (P < 0.001, P < 0.001, P=0.003, P < 0.001 and P < 0.001 respectively). However, the decreases of other dyspepsia symptoms scores from baseline in the extract group were not significant compared to the placebo (P> 0.05). The extract improved the quality of life measured by the SF-36 questionnaire significantly compared to the placebo and baseline (P=0.003 and P < 0.001 respectively). Moreover, the extract lowered the rate of H. pylori infection determined by the urease test significantly compared to the placebo and baseline (P=0.001 and P < 0.001 respectively). The extract did not significantly affect the complete blood count and liver and kidney function tests (P > 0.05). The patients did not experience any adverse drug effect. Conclusions: M. pulegium extract (genuine drug extract ratio: 19.4:1; extraction solvent: 70% v/v aqueous ethanol) 270 mg three times daily taken for 2 months as adjunct to one famotidine 40 mg tablet per day seems safe, improves dyspeptic symptoms and quality of life and eradicates H. pylori in functional dyspepsia patients.