Therapeutic use of Saint John’s wort in RLS/Willis Ekbom’s disease

Abstract

Introduction Different classes of drugs alleviate symptoms of RLS/Willis Ekbom’s disease (WED), whereas others may aggravate them: drugs that worsen symptoms usually inhibit the CYP4503A4 isoform, and drugs that ameliorate them induce CYP4503A4. The main objective of this study was to verify whether Saint John’s wort (SJW), as an inducer of the CYP4503A4 isoform, would reduce the severity of RLS symptoms. Materials and methods Over the course of three months, in an open-label pilot trial, we treated 21 patients (12–76 years; median 48 years), with clinical criteria for RLS with a concentrated extract of Saint John’s wort at a daily dose of 300mg. Hb, Ht, TSH and T4 levels were normal in all patients; eight patients had ferritin levels under 45ig/L (after the end of the trial they also received iron therapy). No side effects with SJW were reported. Results Saint John’s wort reduced the severity of symptoms of WED in 17 of the 21 patients. Their median WED severity score, according to the International Restless Legs Syndrome Study Group (IRLSSG), ranged from 17 to 36 (median 24). After the initial ten-day treatment, 17 patients (81%) reported experiencing >70% improvement of their WED symptoms and also reported better sleep during treatment compared to before treatment. Four patients reported no improvement during the ten-day trial, all of whom were drug-naive (median WED severity score of 24). All patients whose symptoms were alleviated by the ten-day SJW trial agreed to take the drug for three more additional months. Following cessation of the drug, they reported that they remained free of WED symptoms for 2–7 days (median 3). After completing the three- month trial, all 17 patients reported a desire to continuously take SJW as a WED treatment. At the beginning of the trial, these 17 patients scored a median of 24 ( ± 5.1 ) points in the IRLSSG rating severity scale, and after the three-month treatment, the score was 4.1 ( ± 1 ) (p Conclusion Results of this trial suggest that Saint John’s wort may be useful for some RLS patients. Thus, the extent to which Saint John’s wort is effective as a WED treatment will depend on future blind placebo-controlled studies. Acknowledgements Jundiai Medical School.