Cardiopulmonary bypass (CPB) is known to have important effects on the disposition of drugs, which in turn may have important implications for the efficacy and toxicity of drug therapy. These effects constantly change throughout CPB and some continue to exert influence after the patient has been successfully weaned. In children, developmental and disease specific changes in drug disposition and effect also need to be taken into account when studying the effects of CPB. This review will provide an extensive overview of the current literature concerning the mechanisms behind the effects CPB has on pharmacokinetic and pharmacodynamic parameters. Also the effects of CPB on individual anesthetic drugs and sedatives, opioids, neuromuscular blocking agents, antibiotics and miscellaneous medications will be reviewed. Special attention will be paid to the pediatric population.