List of products in the National Drug Code with proprietary name . Daclatasvir is used with another antiviral medication (sofosbuvir) to treat chronic (long-lasting) hepatitis C, a viral infection of the liver. Daclatasvir should never be used without sofosbuvir. Daclatasvir and sofosbuvir may also be used with another antiviral medication (ribavirin). These medications together reduce the amount of hepatitis C virus in your body, which helps your immune system fight the infection and may help your liver recover. Chronic hepatitis C infection can cause serious liver problems such as scarring (cirrhosis), or liver cancer. It is not known if this treatment can prevent you from passing the virus to others. Do not share needles, and practice "safer sex" (including the use of latex condoms) to lower the risk of passing the virus to others.