St. John's Wort is ineffective at alleviating symptoms of attention deficit hyperactivity disorder in children and teenagers, a new study says.

According to a study, published in the June 11 issue of the Journal of the American Medical Association, subjects with ADHD who were treated with St. John's Wort did not have a greater improvement in symptoms compared to subjects who took a placebo.

When measuring symptoms on an ADHD rating scale, the researchers found:

  • Inattentiveness improved 2.6 points among patients taking St. John's Wort and 3.2 points among the placebo group.
  • Hyperactivity improved 1.8 points among St. John's Wort subjects and 2.0 points among subjects who took the placebo.

"The results of this study suggest that administration of St. John's Wort has no additional benefit beyond that of placebo for treating symptoms of child and adolescent ADHD," the authors concluded.

The findings raise doubts about the effectiveness of alternative therapies to treat children's ADHD. Background information included in the study said that up to 30 per cent of children in the United States who have ADHD do not respond to pharmaceutical medications, or suffer side effects such as nausea, insomnia or weight loss.

Some alternative treatments include dietary changes or supplements, massage and herbal remedies, including St. John's Wort, Echinacea and Ginkgo biloba, the study's authors wrote.

St. John's Wort is a popular natural sleep and relaxation aid, and has had mixed results in studies that have analyzed its effectiveness in treating depression in adults.

Wendy Weber, PhD, of Bastyr University in Kenmore, Wash., and colleagues studied 54 kids with ADHD between the ages of 6 and 17. Twenty-seven subjects were instructed to take 300 mg of St. John's Wort three times a day for eight weeks. The other 27 subjects took the same dose of a placebo over the same time period.

The researchers also found the proportion of subjects who experienced one or more side effects, such as rash, nausea, headache or sunburn, was almost the same between the two groups: 40.7 per cent of the St. John's Wort group versus 44.4 per cent of the placebo group.

Abstract:

Hypericum perforatum (St John's Wort) for Attention-Deficit/Hyperactivity Disorder in Children and Adolescents: A Randomized Controlled Trial

Wendy Weber, ND, PhD, MPH, Ann Vander Stoep, PhD, Rachelle L. McCarty, ND, MPH, Noel S. Weiss, MD, DrPH, Joseph Biederman, MD, Jon McClellan, MD

Context Stimulant medication can effectively treat 60% to 70% of youth with attention- deficit/hyperactivity disorder (ADHD). Yet many parents seek alternative therapies, and Hypericum perforatum (St John's wort) is 1 of the top 3 botanicals used.

Objective To determine the efficacy and safety of H perforatum for the treatment of ADHD in children.

Design, Setting, and Participants Randomized, double-blind, placebo controlled trial conducted between March 2005 and August 2006 at Bastyr University, Kenmore, Washington, among a volunteer sample of 54 children aged 6 to 17 years who met Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) criteria for ADHD by structured interview.

Intervention After a placebo run-in phase of 1 week, participants were randomly assigned to receive 300 mg of H perforatum 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.

Main Outcome Measures Performance on the ADHD Rating Scale-IV (range, 0-54) and Clinical Global Impression Improvement Scale (range, 0-7), and adverse events.

Results One patient in the placebo group withdrew because of an adverse event. No significant difference was found in the change in ADHD Rating Scale-IV scores from baseline to week 8 between the treatment and placebo groups: inattentiveness improved 2.6 points (95% confidence interval [CI], −4.6 to −0.6 points) with H perforatum vs 3.2 points (95% CI, −5.7 to −0.8 points) with placebo (P=.68) and hyperactivity improved 1.8 points (95% CI, −3.7 to 0.1 points) with H perforatum vs 2.0 points (95% CI, −4.1 to 0.1 points) with placebo (P=.89). There was also no significant difference between the 2 groups in the percentage of participants who met criteria for improvement (score _2) on the Clinical Global Impression Improvement Scale (H perforatum, 44.4%; 95% CI, 25.5%-64.7% vs placebo, 51.9%; 95% CI, 31.9%-71.3%; P=.59). No difference between groups was found in the number of participants who experienced adverse effects during the study period (H perforatum, 40.7%; 95% CI, 22.4%-61.2% vs placebo, 44.4%; 95% CI, 25.5%-64.7%; P=.78).

Conclusion In this study, use of H perforatum for treatment of ADHD over the course of 8 weeks did not improve symptoms.