Oseltamivir: a clinical and pharmacological perspective

Abstract
Oseltamivir is the ethyl ester prodrug of the antiviral molecule, oseltamivir carboxylate, a potent and selective inhibitor of influenza A and B neuraminidase (NA) (sialidase). It is highly bioavailable in capsule and suspension formulations and, after conversion to the active metabolite in the liver, distributes throughout the body, including the upper and lower respiratory tract. Oseltamivir carboxylate is 3% bound to human plasma proteins and eliminated through the kidneys by a first-order process as unchanged drug by glomerular filtration and tubular secretion by an anionic transporter system. Given these characteristics, its potential for adverse interactions with other drugs appears limited to those arising from competitive inhibition of excretion by the renal tubular epithelial cell anionic transporter. The terminal plasma elimination half-life is 1.8 h in healthy adults. Renal clearance is inversely related to renal function and averages 23 h after oral administration in individuals with creatinin...