Genes Control Response to AD/HD Medication

Research shows that a blood test may reveal how well people with AD/HD respond to medication.

A simple blood test to predict how well people with AD/HD respond to medication may be in the offing. That's the possible implication of new research showing that children's response to methylphenidate (Ritalin) depends upon whether they have inherited a particular gene that regulates the neurotransmitter dopamine.

"It's often difficult to know how patients will respond to AD/HD medications," said Mark Stein, M.D., director of the Hyperactivity, Attention, and Learning Problems Clinic at the University of Illinois at Chicago and the lead author of a study involving 47 children with AD/HD between five and 16 years of age. "Our hope is to take a lot of the guesswork out of why some people respond to these medications and others do not."

Dr. Stein found 60 percent of the children with the more common form of the dopamine transporter gene had an excellent response to medication. None of the children with a less common variant of the gene responded as well.

Stein said more research is needed before doctors will be able to routinely test their patients' likely response to medication.