Written by Marcia J. Egles, MD. In a placebo-controlled, double-blind pilot study, 30 mg of zinc per day had amphetamine dosages lowered by 37 % as compared to the placebo-amphetamine group.
Attention Deficit Hyperactivity Disorder, or ADHD, is a diagnosis commonly given to children. According to the Center for Disease Control (CDC), approximately 11% of American children 4-17 years of age (6.4 million) have been diagnosed with ADHD as of 2011(2). The symptoms of ADHD include lack of focus, hyperactivity and impulsivity. As compared to their peers, children with ADHD experience higher rates of unintentional injury, peer problems and academic failure (3).
The most widely used treatments for ADHD include stimulant medications such as methylphenidate (Ritalin) or amphetamine. While many children experience good response to these treatments, others do less well or suffer from side effects as dosages increase to control symptoms. A preliminary study from the University of Ohio suggests that zinc supplements might be beneficial for children receiving stimulant treatments for ADHD (1).
Prior studies done in the Middle East where zinc deficiency is prevalent, have noted improvements in ADHD symptoms when zinc supplements have been used alone or as adjuncts to stimulant treatments (4, 5). Zinc deficiency in the Middle East is thought (1) to be related to poor mineral soil conditions and to the high consumption of unleavened whole grain breads and beans in which might bind the zinc. A diet rich in zinc might be more varied and include whole grains, meat, shellfish, poultry, nuts and dairy products. The Ohio study was performed in a population not appreciably deficient in zinc (1).
The placebo-controlled, double-blind pilot study consisted of three phases in which 52 children between the ages of 6 and 14 were recruited from the Ohio University child psychiatric clinic. All had been diagnosed with ADHD. The children were randomly divided into zinc treatment groups and a control group. In the first eight-week phase of the trial, 16 children received 15 mg per day of zinc in the form of zinc glycinate tablets to be swallowed each morning. Twelve children received 15 mg zinc (zinc glycinate) twice a day. The other 24 children received placebo tablets instead of zinc.
In the second phase, for 2 weeks, all the children received a fixed dose of extended-release daily generic amphetamine added to the zinc or to the placebo. Those weighing less than 25 kg received 5 mg of amphetamine. Those 25kg to 45 kg received 10mg amphetamine per day. Those over 45kg received 15mg/day. In the third phase, lasting 3 more weeks, the zinc or placebo was continued, but the dose of amphetamine could be adjusted higher or lower based on the child’s symptoms.
For the first phase with zinc treatment alone, there was no superiority of zinc when compared to placebo for control of ADHD symptoms. For the second phase, the symptoms of the zinc treated children receiving amphetamine were comparable to the symptom scores of those receiving amphetamine and no zinc supplements. However, in the final phase, those who received 30mg of zinc per day had amphetamine dosages lowered by 37% as compared to the placebo-amphetamine group. The 15 mg zinc group saw no significant reductions in amphetamine dosage.
The dosages of zinc chosen for the study were based upon amounts that assured meeting the recommended daily allowance but low enough to avoid toxicity issues. Extensive evaluations of zinc status at baseline and throughout the study were conducted (1). No untoward side effects to zinc supplementation were observed.
In this study, zinc supplementation did appear to lower the dosage of amphetamine which produced optimum symptom control. The study results are of a preliminary nature and only notable for a three-week period. Clearly a longer study would be desirable. This pilot study was reported in 2011 with no follow-up study yet published.
Source: “Zinc for Attention Deficit/Hyperactivity Disorder: Placebo-Controlled Double-Blind Pilot Trial Alone and Combined with Amphetamine” by L.Eugene Arnold, MD et al in Journal of Child and Adolescent Psychopharmacology, Vol. 21 No. 1, 2011.(1) Posted January 16, 2014. r/ah
- Arnold, L. Eugene et al. Zinc for Attention Deficit/Hyperactivity Disorder: Placebo-Controlled Double-Blind Pilot Trial Alone and Combined with Amphetamine. Journal of Child and Adolescent Psychopharmacology, Vol. 21.No 1, 2011.
- Centers for Disease Control and Prevention (CDC) website, Attention Deficit/Hyperactivity Disorder (ADHD) Data & Statistics.
- Visser, Susan N. Melissa L. Danielson, Rebecca H. Bitsko, Joseph R. Holbrook, Michael D. Kogan, Rheem M. Ghandour, Ruth Perou, Stephen J. Blumberg .Trends in the Parent-Report of Health Care Provider-Diagnosed and Medicated ADHD Disorder: United States, 2003—2011. J Am Acad Child Adolesc Psychiatry. 2013 [published online November 22] doi: 10.1016/j.jaac.2013.09.001.
- Uckardes Y. et al: Effects of zinc supplementation on parent and teacher behavior rating scores in low socioeconomic level Turkish primary school children. Acta Paediatr 98: 731-736. 2009.
- Akhondzadeh S et al : Zinc sulfate as an adjunct to methyphenydate for the treatment of attention deficit hyperactivity disorder in children: A double-blind and randomized trial (ISRCTN64132371). BMJ Psychiartry 4:9, 2004.