The patients in whom the hemoglobin falls by more than 2 g per deciliter are followed every 2 weeks until stabilization. The dose of ribavirin is reduced to 600 mg per day in patients whose hemoglobin concentrations fall below 10 g per deciliter, and it is discontinued if the concentration falls below 8.5 g per deciliter. For severe adverse events other than anemia, the dose of interferon is reduced in half and the dose of ribavirin to 600 mg per day. The full dose can be resumed after the event, or discontinued if the effect persists.