ADHD unaffected by 8-week course of St. John's wort.

An 8-week course of St. John's wort did not improve attention-deficit/hyperactivity disorder symptoms in what researchers described as the first-ever randomized clinical trial of the herbal remedy in children and adolescents, according to a report in JAMA.

Compared with placebo, St. John's wort--one of the three most common herbal treatments for ADHD in the pediatric population--did not improve hyperactivity, impulsivity, or inattentiveness, reported Wendy Weber, Ph.D., of Bastyr University's School of Naturopathic Medicine, Kenmore, Wash., and her associates.

As many as 30% of children with ADHD fail to respond to, or cannot tolerate, pharmaceutical medicine for the disorder, so many parents turn to complementary or alternative medicines. St. John's wort (Hypericum perforatum) has been found to inhibit the reuptake of norepinephrine, so in theory it might be beneficial in ADHD.

Dr. Weber and her associates studied 54 healthy subjects aged 6-17 years who met DSM-IV criteria for ADHD based on structured diagnostic interviews. Half the subjects were randomly assigned to take a 300-mg capsule of St. John's wort, and the other half were to take placebo capsules, three times daily (before school, after school, and before bed), for 8 weeks. ADHD symptoms were assessed at office visits at baseline and every 2 weeks thereafter using the ADHD Rating Scale-IV, an 18-item standardized instrument for weekly assessment of treatment response. The Clinical Global Impression Improvement Scale also was used at weeks 4 and 8 to evaluate whether global impairment worsened, remained steady, or improved.

The treatment's potential effect on other behavioral problems was assessed using the Child Behavior Checklist and Youth Self Report Form. Parents also reported their assessments of ADHD symptoms by completing the Con-ners' Parent Rating Scale at baseline and at the conclusion of the study.

Finally, changes in quality of life were evaluated using the PedsQL form.

Possible adverse effects were tracked using a measure of 76 potential adverse effects. There were no significant differences between the two groups in ADHD symptoms on any assessment, either in the intention-to-treat analysis or the per-protocol analysis, Dr. Weber and her associates said (JAMA 2008;299:2633-41).

The subset of children who had never taken pharmaceutical medication for ADHD before this study also showed no improvement beyond that achieved with placebo, the investigators added.

The study was supported by grants from the National Center for Complementary and Alternative Medicine, an agency of the National Institutes of Health. Dr. Weber reported no conflicts of interest.

BY MARY ANN MOON

Contributing Writer