Therapy for HCV has been successful even when patients have not abstained from continued
drug or alcohol use or are receiving daily
methadone.
Methadone treatment has been shown to reduce risk behavior that can spread HCV or impair adherence to treatment, and it is not a contraindication to HCV treatment. However, current data suggest that elevated levels of HCV replication, caused by opiates and their withdrawal, may impair responses to interferon.