The volume of distribution of ribavirin is large (2000 L/kg) and the length of time the drug is trapped varies greatly from tissue to tissue. The mean
half-
life for multiple doses in the body is about 12 days, but very long-term kinetics are dominated by the kinetics of RBCs (half-life 40 days). RBCs store ribavirin for the lifetime of the cells, releasing it into the body's systems when old cells are degraded in the spleen.
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