Millions of children are given ADHD drugs such as methylphenidate (Ritalin) to help them to deal with their attention deficit hyperactivity disorder (ADHD), and for some of them, it can really help with their ability to focus and concentrate. This drug has been used for decades now, so researchers have a lot of information to look at when it comes to weighing its pros and cons.

One study, which started in 1994, tracked 579 children with ADHD. The children were treated in different ways with some getting counseling, some getting a drug such as Ritalin, some getting both, and some getting neither. After 36 months, the researchers noted that those children who were given the drugs were growing more slowly than those who did not get the drug. They believed that this height gap would likely resolve itself as the children went through adolescence.

The team followed up with the children in the study nine years later, however, and found that they remained, on average, shorter by about 1.6 inches. In 2017, the scientists involved with the study published a follow-up paper that tracked the height (and other things) about the children in the study until they were 25-years-old.  The height gap remained.

Other researchers analyzed 18 separate studies conducted on children who took Ritalin and found similar results. Kids who are given this drug are typically shorter and weigh less than those who don’t. The researchers do not know the mechanism behind this effect, however. Some suggest that it is because this type of drug tends to suppress appetite, but there was no indication that the children were in any way malnourished, so that would not explain the dramatic differences in size.

This calls into question whether Ritalin and other similar drugs are appropriate for children to be taking. In some cases, the benefits that they receive may outweigh the potential issues in size. The problem, however, is that research has shown that the benefits of Ritalin typically stop after about a year of use. In addition, time has shown that there are no clear benefits in academic performance for the kids who were given this drug.

While this is not enough data to discontinue the use of this type of drug entirely, it should certainly give pause to parents and doctors when thinking about using it. In some cases, it may be appropriate, but given this information, it is likely overprescribed.

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