Yes or No?: Does ADHD Stimulant Medication Suppress Growth?
Parents with children who have ADD or ADHD often weigh the benefits of medication with the possible side effects of the stimulant drugs. Even though research has shown that the best outcomes for children with ADHD comes from a combination of medication and behavioral therapy, many parents agonize about the side effects of medication, specifically the impact on a child's long-term growth.
Getting a definitive answer has not been easy. Yes, Ritalin and its derivatives have been among the most widely studied classes of drugs indicated for children. But the answers have been murky at best.
Dr. Bruce Friedman, child, adolescent and adult psychiatrist from Montclair, N.J., says that just in the years he attended medical school the pendulum has swung back and forth four times. "Yes, no, yes, no... it was never clear whether there was an effect on growth."
But he has confidence in the latest ADHD meds research published in June 2010 in the Journal of Pediatrics by Biederman, Thomas, Spencer, Monuteaux and Faraone because it is a prospective study following children into adulthood. While in the past, many of the studies reported findings after a year or three years, this newest report is a 10-year comparison of children with and without ADHD. It examines whether ADHD itself affects growth, as well as the effects of stimulant treatment. And what the study found is that there is no evidence that either ADHD, or medication to treat it, has any effect on trajectories of height over time.
Fact or Fiction?
So where did the previous findings come from? When studies were done after a year of treatment, or three years, statistically significant delays were reported. Meaning, kids with ADHD, whether or not they were on stimulant medication, were half an inch to an inch-and-a-half shorter than their non-ADHD peers. Yet their data was captured before they were done growing. Taking a longitudinal approach shows that the difference is in the growth process, and not the ultimate adult growth parameters.
"If you were to follow the growth in boys from age 8 to 18, you'd typically see a spike at around age 13. Then after a couple of years, the growth would level off," says Dr. Friedman. But the typical growth pattern of a boy on stimulant medication does not spike early into adolescence and continues on a more gradual incline. And both lines, according to the studies, end up in the same place.
It appears from the research that children with ADHD, whether or not they are on stimulant medication may be shorter than their peers during their teen years. And the doctors who performed these studies suspect that it is ADHD itself, and not necessarily the treatment of it, that may cause the delay in growth. Yet many parents worry that adolescence is hard enough - without adding in the potential of their child being on the smaller side - and make growth a factor in deciding whether or not to medicate.
"Parents should look at the crucial benefits of treating ADHD -- including improved attention, improved learning both in and out of class, better social skill development, diminished risk of mood disorders like depression, and better self-esteem. The question is, 'do I want my child to attain his or her full height at the expense of diminished development in so many other areas?'"
Fortunately, as Dr. Friedman believes, the most recent and highly valid study eliminates that question because there is no demonstrated effect of stimulant treatment on final height. "It is a win-win scenario," he says.
Read our article What's it Like to Have ADHD?
Read our article ADHD: What Parents Need to Know