Therapeutic Effects of Standardized Formulation of Stachys lavandulifolia Vahl on Primary Dysmenorrhea: A Randomized, Double-Blind, Crossover, Placebo-Controlled Pilot Study

Objectives: In Iranian folklore medicine, boiled extract of Stachys lavandulifolia Vahl is reputed to have therapeutic effects in painful disorders. This study evaluated the efficacy of the standardized formulation of S. lavandulifolia Vahl in reducing pain in primary dysmenorrhea, which is known to be a common disorder with significant impact on quality of life. Design: A randomized, double blind, crossover, placebo-controlled pilot study. Settings/Location: Bu-Ali Hospital affiliated with Tehran Medical Branch, Islamic Azad University. Subjects: Twenty-nine patients with primary dysmenorrhea. Patients were enrolled according to medical history and gynecologic sonography. Interventions: Standardized capsules of S. lavandulifolia were prepared. All the patients were allowed to take mefenamic acid up to 250 mg/q6h if they needed, in the first menstruation cycle to estimate the analgesic consumption at baseline. By the use of an add-on design in the next cycle, they were randomly assigned to receive either herbal or placebo capsules every 4-6 h. Then, they were crossed over to the other group during the course of the trial. Outcome measures: At the end of the fourth day of each cycle, the intensity of pain was measured by visual analogue scale and McGill pain questionnaire. Statistical significance was evaluated using repeated-measures one-way analysis of variance. Results: Pain intensity was significantly decreased during consumption of Stachys lavandulifolia capsules in comparison with basic and placebo cycles (p < 0.05). Interestingly, the consumption of mefenamic acid capsules was reduced dramatically in the S. lavandulifolia cycle in comparison with basic and placebo cycles (p < 0.001). Conclusions: It was demonstrated that S. lavandulifolia-prepared formulation can reduce menstrual pain, and can probably be recommended as an add-on therapy or even an alternative remedy to nonsteroidal anti-inflammatory drugs (NSAIDs) with fewer side effects in primary dysmenorrhea.