Varenicline

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]