Ritalin Doesn't Cause Addiction

Hyperactive boys treated with drugs such as Ritalin were much less likely to abuse alcohol and other drugs as teen-agers than similar boys who had not been treated, researchers say.

Some experts not involved in the study said it was flawed and too small to reach meaningful conclusions.

But authors of the study which involved 212 boys, including 75 with attention-deficit hyperactivity disorder, or ADHD said the findings should help allay concerns that giving children potentially addictive drugs such as Ritalin may promote harmful habits later.

An estimated 3 million school-age children have ADHD, and as many as half may be taking Ritalin or other stimulants, past research indicates.

"There has been a mythology that the use of these medications could `prime' children to become addicts in the future or could develop `a culture of drug taking,'" said Dr. Joseph Biederman of Massachusetts General Hospital, lead author of the study. It is published in the August issue of Pediatrics' Electronic Pages," an Internet extension of the journal published by the American Academy of Pediatrics.

"We believe that children with ADHD who are medically treated will have fewer problems resulting from their disorder and more successful lives, probably giving them fewer reasons to experiment with substance abuse," he said.

Ritalin acts on dopamine, a brain chemical that helps regulate thinking. It is believed to calm hyperactivity by helping children's brains disregard distracting stimuli, such as classroom noise, so they can focus on learning.

The subjects for the research were part of a previous study of families with an ADHD child and families with no ADHD children. The children and their mothers were interviewed on three occasions when they entered the study, one year later and four years after enrollment.

The authors studied 56 ADHD patients who were on medication, 19 DHD patients not on medication and 137 patients without the disorder.

At the study's end, 75 percent of the unmedicated ADHD subjects had substance abuse disorders, compared with 25 percent of the medicated subjects. Abused substances included alcohol, marijuana, hallucinogens, cocaine and other stimulants. Eighteen percent of the non-ADHD subjects were substance abusers.

A critic of the study, psychologist Nadine Lambert of the University of California at Berkeley, said it was too small to show significant differences in rates of drug abuse.

Her own research involving more than 200 ADHD subjects tracked for more than 20 years shows that those who took stimulant medication were more likely to be cocaine and tobacco abusers as adults than non-medicated subjects, she said.

Lambert said she is not opposed to treating ADHD youngsters with stimulants because the benefits have been shown clearly, but she believes there are risks and they should be acknowledged.