RESUMO
We experienced anesthesia care for two patients taking methylphenidate (Ritalin), which is a central nervous system stimulant of amphetamine analogues, usually administered for narcolepsy or refractory depression. The proper dose of methylphenidate is 20-60 mg per day. General anesthesia with epidural anesthesia was administered to both cases for total hip replacement. One patient could discontinue taking methylphenidate five days before the operation, but the other patient could not. Both cases needed more anesthetics than usual on induction, but very stable condition could be maintained during and after the operations. We consider that it is possible to perform general anesthesia safely for patients taking a usual dose of methylphenidate.