This is according to a study that was published this week in The Journal of the American Medical Association.
Hypericum perforatum, also called St. John's wort, is a flowering plant often used in alternative medicine to treat depression. Many studies have been used to test its efficacy for this and other indications. Its active chemical is called hypercin, and some of its efficacy is attributed to this substance.
The study was carried out by Wendy Weber and colleagues from Bastyr University, Kenmore, Washington. They looked at 54 children between the ages of six and 17. 27 of the children were randomly assigned to receive 300 mg of H. perforatum standardized to 0.3% hypercin, while the other 27 received a matched placebo. Treatment was administered three times daily for eight weeks while all other ADHD medications were forbidden.
No significant difference was found between the two groups in terms of ADHD rating scale scores related to inattentiveness and hyperactivity in any of the eight weeks of trials. There was also no difference found in the proportion of participants rated either much or very much improved in relation to ADHD symptoms on a second, different measurement scale called the Clinical Global Impression Improvement Scale. This means that the efficacy of St. John's wort is similar to that of a placebo.
