Varenicline is completely absorbed orally and not affected by food. Steady state is reached within four days of administration. The time to reach maximum concentration is three to four hours. Varenicline exhibits linear kinetics. Varenicline has low protein binding (≤20%) and is not metabolized, unlike nicotine, which undergoes hepatic metabolism by cytochrome P-450 (CYP) isoenzyme 2A6. Most of the drug (92%) is excreted unchanged in the urine via glomerular filtration and active tubular secretion via organic cation transporters. Varenicline has a half-life of 24 hours. Mild renal failure does not affect varenicline's area under the concentration-time curve (AUC), though moderate to severe renal failure does increase the AUC 1.5-2-fold. However, this increase in the AUC is not thought to be clinically significant.
Am J Health Syst Pharm. 2007;64(13):1381-1384. © 2007 American Society of Health-System Pharmacists
Cite this: Varenicline: The Newest Agent for Smoking Cessation - Medscape - Jul 01, 2007.