The study, by researchers at the Institute of Pharmaceutical Chemistry at Germany's University of Munster, suggests that Pycnogenol, an antioxidant plant extract from the bark of the French maritime pine tree, balances stress hormones, which lowers adrenaline and dopamine, resulting in a decrease of ADHD.
"Pycnogenol's ability to naturally treat symptoms of ADHD is what makes this extract exceptionally pleasing to parents who may be uneasy about medicating their children with stimulant medications," said Dr. Peter Rohdewald of the Institute of Pharmaceutical Chemistry at Germany's University of Munster and one of the authors of the study.
The study sampled 57 outpatients with ADHD with an average age of 9 years, from the Department of Child Psychology at the Children University Hospital in Slovakia.
Forty-one patients received Pycnogenol and 16 received placebo. Patients were not supplemented with any other drugs or with vitamins E or C during the study. Participants in the Pycnogenol group received 1 milligram of Pycnogenol or placebo for every kilogram of body weight, on a daily basis each morning, for one month.
Stress hormones were quantified from urine samples of the children taken before and after supplementation with either Pycnogenol or the placebo for a one-month period. After a one-month discontinuation of treatment, a third urine sample was taken that revealed that ADHD symptoms had recurred. The stress hormone levels had increased again during the period when children had stopped taking Pycnogenol, suggesting the effect of Pycnogenol on stress hormones accounts for the improvement of inattention and hyperactivity of the children.
The results revealed that Pycnogenol lowers stress hormones by 26.2 percent in the case of adrenaline and decreases neurostimulant dopamine by 10.8 percent, which plays an important role in brain physiology involving learning, cognition, attention and behaviour.
"The findings acknowledge that children with ADHD have dramatically elevated levels of stress hormones known to increase heart rate and blood pressure, causing excitement, arousal and irritability, as compared to children without ADHD symptoms. The findings of this study demonstrate a significant stress hormone lowering effect for a nutritional supplement for the first time," said Dr. Rohdewald.
The researchers also found that ADHD recurred after a one-month discontinuation of Pycnogenol treatment.
The study is due to be published in an upcoming issue of the journal Nutritional Neuroscience.