A pilot study of Hypericum perforatum for the treatment of premenstrual syndrome

To investigate whether Hypericum perforatum could relieve symptoms of premenstrual syndrome in a small group of women in order to establish a hypothesis and to test methods for conducting a future randomised controlled trial.

Prospective, open, uncontrolled, observational study.

Department of Complementary Medicine, University of Exeter.

Nineteen women with premenstrual syndrome who were in otherwise good physical and mental health and not taking other treatments for premenstrual syndrome.

Volunteers underwent a preliminary screening interview, completed Daily Symptom Ratings for one cycle, and attended a medical screening visit before being diagnosed with premenstrual syndrome. Participants took hypericum tablets for two complete menstrual cycles (1 x 300 mg hypericum extract per day standardised to 900 microg hypericin).

Symptoms were rated daily throughout the trial using a validated measure. The Hospital Anxiety and Depression scale and modified Social Adjustment Scale were administered at baseline and after one and two cycles of treatment.

There were significant reductions in all outcome measures. The degree of improvement in overall premenstrual syndrome scores between baseline and the end of the trial was 51%, with over two-thirds of the sample demonstrating at least a 50% decrease in symptom severity. Tolerance and compliance with the treatment were encouraging.

The results of this pilot study suggest that there is scope for conducting a randomised, placebo-controlled, double-blind trial to investigate the value of hypericum as a treatment for premenstrual syndrome.