Prolonged cholestasis after cyproheptadine-induced acute hepatitis

We report a patient in whom cyproheptadine-induced hepatitis was followed by prolonged cholestasis marked by elevation of serum alkaline phosphatase levels, gammaglutamyltransferase and bile acid levels, and disappearance of small bile ducts. Chlorpromazine and imipramine, which can induce a similar acute hepatitis followed by protracted cholestasis, have a close chemical structure (i.e., a tricyclic ring). We suggest that this structure might be involved in this type of hepatotoxicity.