For his control, Dr Griffiths decided to use methylphenidate hydrochloride, otherwise known as Ritalin, a drug that calms hyperactive children.

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Well, it's about the same price of one year's worth of methylphenidate (brand name: Ritalin), a stimulant often used to treat Attention Deficit Disorder (ADD), a mental processing problem that may affect as many as seven million people in North America alone.

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