Varenicline (Tradename: Champix) is a partial nicotine receptor agonist and antagonist, used for smoking cessation.

  • Varenicline is a partial agonist and antagonist at the alpha-4 beta-2 nicotinic receptor (α4β2 or a4b2) nicotinic acetylcholine receptor (nAChR)[1]
  • Plays a significant role in the nicotine reward pathway[2]
  • Varenicline is safe, tolerable, and efficacious for tobacco cessation in individuals with alcohol use disorder, and might have secondary benefits in reducing alcohol use.[3]
  • Start 1 week before quitting
  • 0.5mg PO qAM x 3 days
  • Increase to 0.5mg PO BID x 4 days
  • Then 1mg PO BID x 3 months
    • Up to 6 months
  • For those with gastrointestinal upset, consider taking medication after eating or with a large glass of water
  • For those with insomnia, consider taking medication earlier in the day.
  • For those who experience side effects, consider reduced dosage (0.5 mg BID)
  • Reports of increased rates of depressed mood, agitation, changes in behaviour, suicidal thoughts and behaviour exist with use of varenicline
  • Clinicians should elicit a psychiatric history prior to using this medication and monitor any changes in mood and behaviour during use
  • From the information available to date, it is not possible to determine whether varenicline increases the risk of heart or stroke events in people who have cardiovascular disease
  • Varenicline was previously thought to increase the risk for neuropsychiatric symptoms, and the FDA applied a black box warning on the medication for this. However, a subsequent 2016 randomized control trial found no significant differences in outcomes between varenicline and placebo, and the warning was removed in 2016.[4][5]