Oct. 26, 2000 (Washington) -- Two new studies are touting the benefits of a potential new drug to treat attention deficit hyperactivity disorder (ADHD). Unlike Ritalin, the new drug, called tomoxetine, is not a stimulant and causes much less side effects than the potentially addictive stimulating drugs.
The researchers looked at close to 300 children with ADHD symptoms, like impulsiveness or inability to focus, and gave them either tomoxetine or a placebo. Some patients also were given Ritalin for comparison. Tomoxetine was given twice a day, before and after school.
After nine weeks of treatment, the researchers say that tomoxetine beat the sugar pill outright and was almost as effective as Ritalin. It helped about 70% of the children. Perhaps, even more important, tomoxetine has less loss of appetite and insomnia than the stimulants.
Since Ritalin is a stimulant, under federal law a new prescription must be obtained every month from the doctor. But since tomoxetine would not have this abuse potential, this new drug would be easier to take should the FDA approve it.
"I think we're very encouraged ... it's nice to talk with the families and the kids and ... they really feel it's effective," Christopher Kratochvil, MD, one of the primary researchers and a child psychiatrist at the University of Nebraska Medical Center in Omaha, tells WebMD.
It's estimated that between 3% to 5% of U.S. children are struggling to overcome attention-related symptoms that can lead to failure in school and social isolation. According to the National Institute of Mental Health, stimulants are by far the most widely used treatments, with some 6 million prescriptions written annually.
What isn't known is how many children go untreated, because their parents fear the stimulants will lead to drug abuse or addiction. In addition, there is controversy within the medical community about whether Ritalin is being overprescribed simply as a tool to control unruly behavior. At least one class-action lawsuit is pending over the manufacturer's alleged failure to disclose some of the drug's major side effects -- a charge that Ritalin's manufacturer, Novartis, denies.
"We're at a point where any drug not called Ritalin is going to have a leg up on Ritalin, because it doesn't carry the name which, of course, has been so pilloried in the media," Russell Barkley, PhD, another of the study's researchers and a professor of psychiatry and neurology at the University of Massachusetts Medical School in Worcester, tells WebMD.
If anything, Barkley and Kratochvil say the studies show that stimulants, which have been used for attention treatments since the 1950s, actually make it less likely children will abuse drugs because the treatments make them less impulsive.
It's believed that two key brain chemicals, dopamine and norepinephrine, play a role in the attention disorders. Stimulants work to enhance both of these neurotransmitters, says Kratochvil, but tomoxetine specifically boosts norepinephrine.
"We will be collecting more data; there are other studies in the pipeline, but certainly this is an excellent start," Kratochvil says.