Varenicline Tartrate is a new molecular entity that received approval from the U.S. Food and Drug Administration in May 2006. It acts at the sites in the brain most affected by nicotine and helps users quit smoking in two ways: by providing some nicotine effects to ease withdrawal symptoms, and blocking the effects of nicotine from cigarettes if smoking is resumed. It is not nicotine, but it binds to the nicotine receptors in the brain, just as nicotine does. Varenicline is not recommended for combination treatment with NRT due to its nicotine antagonist properties.8
Empirical Evidence on Effectiveness
According to a 2008 meta-analysis of 4 studies, it is estimated that 1mg daily of varenicline doubles a smoker's likelihood of long-term abstinence from tobacco compared to placebo. Increasing the dose to 2mg daily approximately triples this abstinence likelihood8 . Data presented at the 2005 meeting of the American Heart Association demonstrated varenicline tartrate to be more effective than bupoprion for smoking cessation over the course of a 12-week trial in two double-blind placebo controlled studies involving 2,000 smokers. In both studies, 44% quit by the end of the 12-week treatment period with varenicline tartrate, compared to 30% of those taking bupoprion. Researchers reported quitting response rates to be three times higher with varenicline tartrate than with placebo.3 The researchers concluded that the significant reductions in craving and in some of the rewarding effects of smoking seen with 1mg of varenicline tartrate twice daily may assist in promoting abstinence and preventing relapse.
Figure derived from Chantix webpage. Click here for more information.
Possible Side Effects
- Flatulence (gas)
- Abnormal dreams
- Dysgeusia (change in taste perception)
Varenicline & Psychiatric Ilness
It is important to note that the clinical trials originally conducted for the approval of varenicline for smoking cessation did not include psychiatric patients. Therefore, the effects of this medication on those with depression, bipolar disorder, and schizophrenia are not yet known. According to the U.S. Department of Health and Human Services Clinical Practice Guideline 2008 Update7, two case reports cited exacerbations of psychiatric illness in patients who took varenicline. In contrast, one recent smoking cessation study using varenicline did include smokers with mental illness and reported no evidence that varenicline worsened symptoms of depression, bipolar disorder, and/or psychosis.8 A warning issued by the FDA in February 2008 recommended that patients tell their health care providers about psychiatric illness history and that clinicians monitor patients for changes in mood and behavior while taking varenicline.9
Links for Brand Names Chantix: http://www.chantix.com
Recommended for 12-weeks, a second 12-week course can be helpful to maintain chances in the long term cessation.
1 Fiore, M.C., et al. (2000). Treating tobacco use and dependence: Clinical Practice Guideline. U.S. Department of Health and Human Services, Public Health Service.
2 Corelli, R.L., & Hudman, K.S. (2002). Medications for smoking cessation. Western Journal of Medicine, 176, 131-35.
3 Gonzales, D., et al. (2006). Varenicline, an a4ß2 nicotinic acetylcholine receptor partial agonist, vs sustained-release Bupropion and placebo for smoking cessation: A randomized controlled trial. Journal of the American Medical Association, 296, 47-55.
4 Tonstad, S. (2002). Use of sustained-release bupropion in specific patient populations for smoking cessation. Drugs, 62, 37-43.
5 Ahluwalia, J.S., et al. (2002). Sustained-release bupropion for smoking cessation in African Americans: A randomized controlled trial. Journal of the American Medical, 288, 497-99.
6 Mooney, S.E., & Sofouglu, M. (2006). Bupropion for the treatment of nicotine withdrawal and craving. Expert Review of Neurotherapeutics, 6, 965-81.
7 Stapleton JA, Watson L, Spirling LI, et al. Varenicline in the routine treatment of tobacco dependence: a pre-post comparison with nicotine replacement therapy and an evaluation in those with mental illness. Addiction 2007;103:146-54.
8 Fiore, M.C, Jaen, C.R., Baker, T.B., et al. (2008). Treating Tobacco Use and Dependence: 2008 Update. Clinical Practice Guideline. Rockville, MD: U.S. Department of Health and Human Services. Public Health Service.
10 West, R., Baker, C.L., Cappelleri, J.C., Bushmakin, A.G. (2008). Effect of varenicline and bupropion SR on craving, nicotine withdrawal symptoms, and rewarding effects of smoking during a quit attempt. Psychopharmacology, 197, 371-377.
11 Williams, K.E., Reeves, K.R. et al. (2007). A double-blind study evaluating the long-term safety of varenicline for smoking cessation. Current Medical Research and Opinion, 23 (4); 793-801.
12 Tonstad, S., Tonnesen, P. et al. (2006). Effect of Maintence Therapy with Varenicline on Smoking Cessation: A Randcomized Controlled Trial. Journal of the American Medical Association, 296: 64-71.
13 Schmitz, J.M., Stotts, A.L. (2007). Buproprion and cognitive-behavioral therapy for smoking cessation in women. Nicotine & Tobacco Research, 9 (7); 785.