The clinical evaluation of the patient with dyslipoproteinemia requires a thorough appraisal of present and past medical history, a review of systems, and physical examination. Any known or suspected medical conditions that might impact on the lipid profile must be explored. This includes an assessment of hypothyroidism, diabetes mellitus, liver disease, and renal disease (nephrotic syndrome). Any pharmacologic agents that may alter the lipids must be identified. This article reviews the drugs currently known to cause dyslipidemia and describes the mechanisms of the effect when known. The drugs are evaluated in four general groups: antihypertensive agents, steroids, drugs used following transplantation, and other drugs.