Interferon is a protein that your body makes to fight infections. Interferon used as a treatment increases the amount of interferon in your body. Interferon can only be given as a shot. You cannot take interferon in a pill. There are two types of interferon used to treat hepatitis C, standard interferon and pegylated interferon.

Standard interferon is given as three shots a week. Pegylated (or long-acting) interferon is given as one shot a week. Which type you get depends on what you and your doctor think will work best for you. Standard (or three times a week) interferon has been used for a long time. Each shot of standard interferon contains 3 million units of the drug. Because of the way drugs are measured, 3 million units sounds like a lot more medicine than it actually is. Pegylated (or once a week) interferon is a newer form. It may give better results in some patients. Some of the side effects of pegylated interferon, including skin reactions, may be worse than with standard interferon. However, some patients find one shot a week to be an advantage. Many things need to be considered before you begin treatment.

Your doctor may need to know more about the amount of the virus in your blood (or viral load) and the type of hepatitis C virus (or genotype) that you have. You should also talk with your doctor about the benefits of standard or pegylated interferon. Together, you can decide what type of treatment is right for you.