The following additional side effects have occurred in HCV/HIV co-infected patients receiving Ribavirin in combination with peginterferon alfa-2b: oral thrush, changes in the amount and distribution of body fat, reduction in the amount of white blood cells, decreased appetite, increase in gamma-glutamyltransferase (an enzyme produced by the liver, associated with early liver cell damage), back pain, increase amounts of amylase (an enzyme present in the blood) and lactic acid, hepatitis, increased lipase (the enzyme necessary for the absorption and digestion of nutrients in the intestines) and limb pain.