Absorption Metabolism and Excretion

Ribavirin can be administered as an aerosol using a small-particle aerosol generator. When administered by this route, the drug has only minimal systemic absorption, with drug concentrations in respiratory tract secretions approximately 100 times as high as those found in plasma. Oral absorption is rapid, and first-pass metabolism is extensive; ribavirin's oral bioavailability is 64% and can be increased by administration with a high-fat meal. Steady-state levels are reached after 4 weeks.

Ribavirin is reversibly phosphorylated by all nucleated cells. It is also metabolized in the liver to a triazole carboxylic acid metabolite that is eliminated in the urine along with the parent compound. The plasma halflife of ribavirin is 9.5 hours when it is administered by aerosol (2.5 hours/day for 3 days), whereas its half-life is around 12.5 days at steady state. The drug accumulates in erythrocytes, with a half-life of 40 days.

Was this article helpful?

0 0
Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

Get My Free Ebook

Post a comment