hypothyroidism , sarcoidosis , systemic lupus erythematosus , rheumatoid arthritis ) in less than 1% of patients. Resistance mechanism disorders (overall: up to 12%), including viral infection (12%) and fungal infection (up to 6%), have been associated with oral ribavirin in combination with peginterferon alfa-2a, peginterferon alfa-2b, or interferon alfa-2b. Side Effects