Methylphenidate works by increasing dopamine levels

Methylphenidate works in the treatment of attention deficit hyperactivity disorder by increasing levels of dopamine in children's brains, according to a study reported in the Journal of Neuroscience(2001;21:121).

Previous research in animals and people had shown that methylphenidate (Ritalin) increases dopamine levels, but the studies involved injections of doses much higher than normally prescribed to children.

To see whether the smaller oral doses of methylphenidate that are usually prescribed to children have the same effects, the researchers, led by Dr Nora Volkow at the Brookhaven National Laboratory in Upton, New York, scanned the …