A mild form of amphetamine used in the treatment of attention-deficit hyperactivity disorder (ADHD), generic name methylphenidate. Ritalin, taken as a pill, also has been effective for the treatment of other conditions such as narcolepsy. Although the drug acts as a stimulant in most people, Ritalin calms and focuses those with ADHD. Ritalin's mode of action is unknown, but it is thought that the drug reduces symptoms by increasing the amount and activity of a neurotransmitter in the brain.
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