Familial male precocious puberty is a form of precocious puberty resulting from an activating mutation of the luteinizing hormone receptor. Behavior problems are associated with the early onset of puberty. In this case, sexual hyperactivity was treated with psychostimulants. Implications for the effectiveness of methylphenidate in reducing sexual hyperactivity with and without familial male precocious puberty are discussed, and testable hypotheses are proposed for the effects of stimulants on sexual behavior in adolescents.