People with attention deficit/hyperactivity disorder (ADHD) who take certain medications over long periods may develop changes in their brains that ultimately impact their ability to respond to the drugs, a new study suggests.
In the study, adults with ADHD had higher levels of a protein called a dopamine transporter in their brains after one year of treatment with the drug methylphenidate (most commonly sold as Ritalin), compared with before they starting taking the drug.
While some researchers have speculated that people with ADHD naturally have more dopamine transporters in their brains, the new study suggests that the high numbers are a result of treatment with medications, said study researcher Dr. Gene-Jack Wang, of Brookhaven National Laboratory in Upton, N.Y. Prior to the study, none of the participants had ever been treated with ADHD drugs.
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