Digital ischemic necrosis caused by pegylated interferon in a patient with hepatitis C.

Pegylated interferon plus ribavirin remains the first-line treatment for patients with hepatitis C virus (HCV). Interferon α has the most extensive clinical application and is used for the treatment of chronic hepatitis B virus and hepatitis D virus as well as acute and chronic HCV infections. The attachment of polyethylene glycol to interferon increases its half-life by reducing the rate of absorption after injection, reducing renal and cellular clearance and also decreasing immunogenicity.