Ribasphere (Ribavirin Tablets) and Anemia

Oral ribavirin may cause anemia. The decrease in hemoglobin generally occurs within 1 to 2 weeks after initiation of therapy and stabilizes by week 4. Because significant anemia may adversely affect cardiac function, oral ribavirin should not be used in patients with severe anemia of any etiology or a history of serious or unstable heart disease. It should also be avoided in patients with hemoglobinopathies such as thalassemia or sickle- cell anemia. Therapy with oral ribavirin may be administered cautiously in patients with stable heart conditions. Both the hemoglobin level and cardiovascular status must be closely monitored. A permanent dosage reduction is required in these patients if the hemoglobin decreases by >= 2 g/dL during any 4- week period. If, after 4 weeks on the reduced dosage, the hemoglobin remains < 12 g/dL, therapy should be discontinued. The drug should also be withdrawn if cardiovascular status deteriorates. For all patients, a dosage reduction is recommended when hemoglobin is < 10 g/dL. If hemoglobin falls below 8.5 g/dL, oral ribavirin should be permanently discontinued. In clinical trials, hemoglobin values generally returned to baseline 4 to 8 weeks after cessation of therapy.