Cytochrome P450 1A2
CYP1A2 is the liver enzyme that clears caffeine, clozapine, and a handful of other drugs. Its activity is shaped by both genetics and lifestyle (smoking speeds it up, certain foods slow it down), but the underlying gene still sets your baseline. About 40 percent of people carry a variant that classifies them as rapid metabolizers; the rest process caffeine at an average or slower rate.[1]
Gene2Rx uses definitions covering 3 named CYP1A2 star alleles, built from 2 variants in Gene2Rx definitions. Results depend on the variants available in your upload.
Star alleles (like *1, *2, *4) are standardized names for distinct versions of a pharmacogene. *1 is the reference; other numbers identify distinct allele definitions. A higher number does not mean lower function.
You inherit one allele from each parent, so your genotype is a pair (e.g. *1/*4). The pair determines your predicted phenotype — for example, whether you metabolize a drug at a normal, decreased, or no-function rate.
PharmVar is the international registry that defines and curates these allele names. Gene2Rx uses the supported definitions summarized here. Coverage depends on the variants present in your input; this is not a guarantee that every cataloged allele can be identified.
This list contains 1 medication with CYP1A2 information from the sources shown below. Evidence and report eligibility differ by drug; each page explains its scope and limitations.
These branded medications include at least one active ingredient whose metabolism or action involves CYP1A2. Each links to its full pharmacogenetic breakdown.
A Gene2Rx report interprets supported variants in the context of your data and purchased report. Missing or uncertain calls may prevent an assessment.
Get your report Look up a medicationInformational only, not medical advice. The presence of a CYP1A2 pharmacogenetic guideline does not mean every patient needs to change their dose. Never start, stop, or change a medication without talking to your prescribing clinician.