HCV infects approximately 2-3% of the global population and is a leading cause of end-stage liver disease and hepatocellular carcinoma. Treatment of HCV infection with Peg-IFN in combination with ribavirin can eradicate HCV infection in 40-90% of patients; however, a major barrier to treatment uptake and delivery is the association of this therapy with frequent and, at times, serious adverse effects. Recognition and effective management of these adverse effects are critical components of the successful treatment of chronic HCV infection. In clinical trials, approximately 10-15% of patients discontinue Peg-IFN and ribavirin therapy due to adverse effects; however, in clinical practice, the rate of treatment discontinuation has been reported to be substantially higher. The off-target effect of Peg-IFN and ribavirin impacts most, if not all, organ systems; the most common adverse effects are hematologic, dermatologic, neurologic, immunologic, gastrointestinal, pulmonary, cardiovascular, and ocular. Regional and global variability exists in the nature of these adverse effects and the strategies employed to ameliorate their impact. This article provides a comprehensive literature review that systematically describes the adverse effects of Peg-IFN-α and ribavirin on various organ systems and, more importantly, recommends consensus approaches to managing those effects. © 2011 Macmillan Publishers Limited. All rights reserved.