Despite there being little clinical evidence suggesting that St. John’s wort was a possibly effective treatment for attention deficit disorder (ADHD), researchers have answered a question nobody asked — St. John’s wort is not any more effective in the treatment of ADHD than placebo. One of the researchers of the study has consulting ties with a pharmaceutical company that offers an FDA-approved medication for ADHD.
Patients treated with either St. John’s wort (Hypericum perforatum) or placebo had similar improvement on the ADHD Rating Scale-IV and the Clinical Global Impression Improvement Scale. The study was led by Wendy Weber, Ph.D., of Bastyr University, a naturopathic medicine institution, and is published in the most recent issue of the Journal of the American Medical Association.
Stimulant medications provide effective treatment for 60% to 70% of children and adolescents with ADHD, the authors said. However, parents often seek alternative therapies, and H. perforatum is one of the most frequently used botanical agents.
Extracts of H. perforatum have yielded mixed results in numerous investigations of its potential as an antidepressant in adults and children, the authors continued. H. perforatum inhibits reuptake of serotonin, norepinephrine, and dopamine.
In the last decade, a new nonstimulant selective norepinephrine reuptake inhibitor, atomoxetine (Strattera), was approved by the FDA for the treatment of ADHD in children and adolescents. Because St. John’s wort is believed to act as a norepinephrine reuptake inhibitor, the researchers thought that perhaps it may also be a beneficial treatment for ADHD.
The latest study was a randomized, double-blind, placebo-controlled trial conducted between March 2005 and August 2006 among a volunteer sample of 54 children aged 6 to 17 years who met the clinical diagnostic criteria for ADHD by structured interview with a trained clinician.
After taking placebo for a week, participants were randomly assigned to receive either 300 mg of St. John’s wort (standardized to 0.3% hypericin (n = 27)) or a matched placebo (n = 27) 3 times daily for 8 weeks. Other medications for ADHD were not allowed during the trial.
No significant differences were found on either outcome measure between the placebo control group and those children taking St. John’s wort.
Because the study was conducted on such a small sample, it is not known whether the results are generalizable, or whether the dosing levels for St. John’s wort were sufficient to create a therapeutic response. Further research into St. John’s wort for ADHD would be needed to rule it out as a possible useful alternative to ADHD stimulant medications.
Source: Journal of the American Medical Association