|Properties:||nicotine receptor partial agonist|
|Hazards:||suicide, hostility, heart problems|
‘’’Varenicline’’’, sold under the brand names Chantix and Champix, is a medication which helps with smoking cessation by blocking nicotine receptors. Some concerns have been raised about possible side effects of the medication, prompting the FDA to add a Boxed Warning for Chantix’s label listing depressed mood, suicidal thoughts, and hostility, similar to warnings associated with Zyban (bupropion), a similar drug. More recently, a meta-analysis of 14 studies reported possible 72% increased risk of heart problems when taking varenicline.
Mechanism of Action
Varenicline binds to neuronal nicotinic acetylcholine receptors, especially to the alpha-4/beta-2 receptor,,, and stops nicotine from binding to these same receptors, thus removing satisfaction typically caused by smoke inhalation. In addition, varenicline is a weak agonist of these receptors, leading to a feeling of relaxation which lessens withdrawal symptoms of smoking cessation.
- Singh, S., Loke, Y.K., Spangler, J.G. and Furberg, C.D. (2011). "Risk of serious adverse cardiovascular events associated with varenicline: a systemic review and meta-analysis". Canadian Medical Association Journal. DOI:10.1503/cmaj.110218. Research Blogging.
- Coe et al (2005) Varenicline: an a4b2 nicotinic receptor partial agonist for smoking cessation. J.Med.Chem. 48 3474.
- Rollema et al (2007) Pharmacological profile of the a4b2 nicotinic acetylcholine receptor partial agonist varenicline, an effective smoking cessation aid. Neuropharmacology 52 985
- Rollema et al (2009) Preclinical pharmacology of the alpha4beta2 nAChR partial agonist varenicline related to effects on reward, mood and cognition. Biochem.Pharmacol. 78 813.
- Singh S, Loke YK, Spangler JG, Furberg CD (2011). "Risk of serious adverse cardiovascular events associated with varenicline: a systematic review and meta-analysis.". CMAJ 183 (12): 1359-66. DOI:10.1503/cmaj.110218. PMID 21727225. PMC PMC3168618. Research Blogging. Review in: Ann Intern Med. 2011 Oct 18;155(8):JC4-5