New Study: Psychostimulants Cause Lasting Changes in Brain Chemistry
A recent study that has appeared in the journal NeuroImage:Clinical, reports that subjects who had been treated with methylphenidate (Ritalin) before the age of 16, had significantly lower levels of the inhibitory neurotransmitter gamma-Aminobutyric acid (GABA) as adults, compared with subjects who had started methylphenidate therapy after age 23, and subjects who had never taken psychostimulants. These results suggest that treatment with psychostimulants in the early stages of human development, when the brain is still developing, can have a significant impact upon the brain chemistry of those individuals later on in life. GABA is the chief neurotransmitter in the brain that serves as an inhibitory agent in the transmission of nerve impulses. The specific region of the brain examined in the study was the medial pre-frontal cortex, an area regarded as important in the origins of ADHD symptoms.
“The prevalence of ADHD has increased rapidly over the last few years,” said Michelle M. Solleveld of the University of Amsterdam, the study’s corresponding author. “With this, prescription rates of methylphenidate, also known as Ritalin, are increasing as well. The safety and efficacy of methylphenidate treatment in adults has been studied thoroughly. However, methylphenidate treatment for ADHD is actually more common in children, and no studies so far have investigated the possible long-term effects of methylphenidate on the developing brain.”
What the actual behavioral and cognitive consequences of this down-regulation in the GABAergic system of the brain would be is still not completely understood. However, the authors noted:
”Although the early MPH [methylphenidate] treatment improves ADHD symptoms, lasting changes in the GABAergic system could have been induced that could e.g. underlie later changes in impulsivity, that in turn, could make patients more vulnerable for risk-taking behavior and/or later drug (ab)use. As such, these data may help to better evaluate decisions regarding treatment of children and adults with ADHD.”
This study should raise a red flag to physicians when it comes to decisions regarding whether or not to medicate a child diagnosed with ADHD. I’ve always believed that medications to treat ADHD symptoms should be used as a last resort, after other non-drug interventions have been tried. ADHD experts are doing parents and children a disservice by promoting medications as a first-line treatment.
My book The Myth of the ADHD Child: 101 Ways to Improve Your Child’s Behavior and Attention Span Without Drugs, Labels, or Coercion, provides a comprehensive list and description of many of the non-drug alternatives that are available for parents and physicians to consider before medication is prescribed.