Researchers at Bastyr University, Kenmore, Washington, have found that kids and teens with attention-deficit/hyperactivity disorder (ADHD) who were treated with the herb St. John's wort did not have any reduction in the severity of ADHD symptoms as compared to those who received a placebo.
For the study, Wendy Weber, N.D., Ph.D., M.P.H., of Bastyr University, Kenmore, Wash., and colleagues conducted a clinical trial of St. John's wort (Hypericum perforatum) on 54 kids and teens with ADHD, age 6 to 17 years, to determine whether this agent was effective in lessening the severity of ADHD symptoms.
During the study, 27 participants were randomly assigned to receive 300 mg of H perforatum standardized to 0.3 percent hypericin (a compound derived from H perforatum) and 27 participants received a matched placebo, three times daily for eight weeks.
The study showed that there were no significant differences between the two groups in the change in ADHD rating scale scores from the start of the trial to week 8 and in change in scores rating inattentiveness and hyperactivity.
Researchers found that there was also no difference in the proportion of participants who were rated as much or very much improved regarding ADHD symptoms on another measurement scale.
No statistically significant difference was found between the two groups in the proportion of participants who experienced 1 or more rash, nausea/vomiting, headache, or sunburn during the trial.
"To our knowledge, this is the first placebo-controlled trial of H perforatum in children and adolescents. The results of this study suggest that administration of H perforatum has no additional benefit beyond that of placebo for treating symptoms of child and adolescent ADHD," the authors said.
The study is published in the June 11 issue of JAMA.