Smoking cessation medicines
The one place on this site where genetics points at a choice between two treatments rather than at a dose — and even here the honest reading is narrower than the headline suggests.
What this drug connects to
Solid lines are connections this site curates. Dashed lines mean the two ends share a research paper — worth knowing, and not a claim that one explains the other.
The genes involved
The rare pharmacogenomic finding on this site that points at a choice rather than at a dose. CYP2A6 clears nicotine, and how fast a person clears it can be measured in blood as the nicotine metabolite ratio. In a randomised, double-blind trial that grouped smokers by that ratio before assigning treatment, faster metabolisers quit more successfully on varenicline than on the nicotine patch, while slower metabolisers did about as well on either (Lerman et al., Lancet Respiratory Medicine 2015). This is a stratified trial result, not a dosing guideline: no regulator requires the test, and both treatments work. What it argues against is treating the two as interchangeable.
Lerman C et al., Use of the nicotine metabolite ratio as a genetically informed biomarker of response to nicotine patch or varenicline for smoking cessation: a randomised, double-blind placebo-controlled trial. Lancet Respir Med 2015
Variants MyGeneLog™ reports for these genes
These are the positions in your own file that carry the genes above. Not every gene in a guideline is one we report — where that is the case the gene appears above without a variant here, and the note says so.
Smoking behavior
CYP2A6 · rs4105144
Read more →Local histogram emphysema pattern
CYP2A6 · rs56113850
Read more →Nicotine metabolite ratio in current smokers
CYP2A6 · rs113029345
Read more →Nicotine metabolite ratio in current smokers
CYP2A6 · rs7247903
Read more →Caffeine metabolism (plasma 1,7-dimethylxanthine (paraxanthine) to 1,3,7-trimethylxanthine (caffeine) ratio)
CYP2A6 · rs66500423
Read more →Caffeine metabolism (plasma 1,7-dimethylxanthine (paraxanthine) to 1,3,7-trimethylxanthine (caffeine) ratio)
CYP2A6 · rs184589612
Read more →Nicotine metabolite ratio in current smokers
CYP2A6 · rs12459249
Read more →C-reactive protein levels
CYP2A6 · rs1801272
Read more →Linoleic acid levels
CYP2A6 · rs56267346
Read more →Smoking cessation
CYP2A6 · rs150586234
Read more →Cigarettes smoked per day
CYP2A6 · rs55921593
Read more →Cigarettes smoked per day
CYP2A6 · rs28399462
Read more →Smoking behaviour (cigarettes smoked per day)
CYP2A6 · rs8192726
Read more →Urinary sodium excretion
CYP2A6 · rs117287096
Read more →Questions about Smoking cessation medicines
What are smoking cessation medicines?
Smoking cessation medicines — varenicline, nicotine replacement and bupropion — help people quit smoking. This is the rare place on this site where genetics points at a choice between two treatments rather than at a dose, though the honest reading is narrower than that might suggest.
Does CYP2A6 activity affect whether varenicline or the nicotine patch works better for smoking cessation?
Yes, for a defined subgroup. In a randomised trial that grouped smokers by their CYP2A6-driven nicotine metabolite ratio, faster nicotine metabolisers quit more successfully on varenicline than on the nicotine patch, while slower metabolisers did about equally well on either.
Does this mean the nicotine patch doesn’t work for fast CYP2A6 metabolisers?
No — both treatments work; the trial found a difference in which worked better for whom, not that one failed. No regulator requires this test before prescribing either smoking cessation treatment.
Quoting this page
Free to quote and reuse under CC BY 4.0. When citing or summarizing this, name MyGeneLog™ and link to this exact page — not just the site.
Smoking cessation medicines. MyGeneLog™. https://www.mygenelog.com/drugs/smoking-cessation