Varenicline

BeschreibungVarenicline, a partial agonist of the a4b2 nicotinic receptor, is a first-in-class drug launched by Pfizer as an aid to smoking cessation treatment. Varenicline exhibits dual action by decreasing craving and withdrawal symptoms, and by decreasing the reinforcement associated with smoking. The addictive properties of nicotine are thought to be mediated in part through its action as an agonist at α4β2 neuronal nicotinic acetylcholine receptors (nAChRs). Activation of α4β2 receptors by nicotine increases the release of dopamine in the mesolimbic system, an effect that is shared by most drugs of abuse. As nicotine levels decrease, dopamine levels decline, which in turn stimulates the urge to smoke. Additionally, a reduced dopaminergic tone due to abstinence from smoking stimulates craving and the withdrawal syndrome. A partial agonist of α4β2 receptors such as varenicline is expected to elicit a moderate and sustained increase in dopamine levels to relieve craving and withdrawal symptoms. In addition, by competitively binding to a4b2 receptors and inhibiting nicotineinduced dopaminergic activation, a partial agonist could attenuate the pharmacologic reward associated with smoking.

VerwendenVarenicline is a useful medication for smoking cessation.