St. John’s Wort May Not Ease ADHD

June 10, 2008 -- Many parents believe that herbal medicines can help children with ADHD focus better and ease other symptoms.

However, a new study shows that in children and teens diagnosed with ADHD, taking St. John’s wort was no better than taking a placebo pill.

Attention deficit hyperactivity disorder affects 3% to 12% of children in the U.S. An article accompanying the study reports that 30% of young people with ADHD do not respond well to prescription drugs.

St. John’s wort is among the most common herbal treatments used for ADHD. There have been plenty of studies (with mixed results) exploring whether St. John’s wort helps lift moderate depression in adults.

Study authors say this is the first placebo-controlled trial to look at whether the popular herbal supplement can help kids with ADHD.

Researcher Wendy Weber, ND, PhD, MPH and colleagues at Bastyr University in Kenmore, Wash., looked at 54 children aged 6 to 17. All were healthy, not taking any other medications (St. John’s wort can interact with other medications) including ADHD prescriptions, and were not diagnosed with severe depression or bipolar disorder.

Half of the participants were randomly assigned to take one capsule containing 300 milligrams of St. John’s wort three times a day for eight weeks.  

The other participants received the same orders, but were given placebo capsules.

The researchers were not aware of which participants were taking the placebo or the St. John’s wort.

St. John's Wort Results

• No significant difference in symptom scores and hyperactivity and inattentiveness scores were found in the group taking St. John’s wort when compared to the placebo group.
• No significant differences were found between both groups when it came to participants who had side effects, like rashes, headaches, sunburn, or nausea.
• The two groups experienced no significant difference in weight gain or height.

New, Improved St. John’s Wort?

The kind of St. John’s wort used in this trial was not “high hyperforin,” which is now on store shelves. Hyperforin is an ingredient in St. John’s wort. Newer supplements contain 3% to 5% hyperforin. The hyperforin content used in this study was 0.14%.

Study authors also write that St. John’s wort may work with other herbals, vitamins, minerals, or supplements.

The researchers call for further study, acknowledging some limitations. The study was small, with 54 participants; and relatively short at eight weeks from start to finish.

In an editorial that appears alongside the study, Eugenia Chan, MD, with Children’s Hospital Boston and Harvard, writes “randomizing participants may be difficult or impossible when the therapy to be evaluated relies on participants’ belief in the treatment or relationship with the practitioner.”

The findings appear in the June 11 edition of The Journal of the American Medical Association.