Is Chlorpheniramine, Ibuprofen and Pseudoephedrine (Advil Allergy Sinus) affected by genetics?
Partially. 1 of 3 ingredients has pharmacogenetic evidence.
Chlorpheniramine, ibuprofen and pseudoephedrine contains 3 active ingredients, and 1 of them has published pharmacogenetic guidelines. The relevant gene is CYP2C9. Your genotype can change how that ingredient behaves in your body, while the other ingredients aren't affected by genetics in any clinically established way. The strongest evidence level on this page is Strong, from the published guidelines shown below.
Also sold as Advil Allergy Sinus.
Pharmacogenetic guidelines are written for one ingredient at a time, so the guidance below is for each ingredient on its own. What your genes mean for a combination product is less clear, because the dose and the other ingredients can change things. If you take Chlorpheniramine, ibuprofen and pseudoephedrine, it's worth talking over with your prescriber or pharmacist. How we handle combination products.
What's in Chlorpheniramine, ibuprofen and pseudoephedrine
Chlorpheniramine No known pharmacogenetics
No strong published pharmacogenetic guideline currently applies to chlorpheniramine.
Ibuprofen Affected by CYP2C9
Affected by CYP2C9. Guidance from CPIC, strong evidence.
Read the full ibuprofen genetics guidePseudoephedrine No known pharmacogenetics
No strong published pharmacogenetic guideline currently applies to pseudoephedrine.
Ibuprofen phenotype recommendations
Published guidance from CPIC on how ibuprofen should be dosed or substituted based on your CYP2C9 phenotype.
| Phenotype | What it means | Recommendation | Evidence |
|---|---|---|---|
| Normal MetabolizerCYP2C9 | Your body processes this drug normally, so the usual starting dose applies. | CPIC Initiate therapy with recommended starting dose. In accordance with the prescribing information, use the lowest effective dosage for the shortest duration consistent with individual patient treatment goals. |
Strong |
| Intermediate MetabolizerCYP2C9 | Your body slows the drug down slightly, but usually the normal starting dose is fine. | CPIC Initiate therapy with recommended starting dose. In accordance with the prescribing information, use the lowest effective dosage for the shortest duration consistent with individual patient treatment goals. CPIC Initiate therapy with lowest recommended starting dose. Titrate dose upward to clinical effect or maximum recommended dose with caution. In accordance with the prescribing information, use the lowest effective dosage for the shortest duration consistent with individual patient treatment goals. Carefully monitor adverse events, such as blood pressure and kidney function, during course of therapy. |
Moderate |
| Poor MetabolizerCYP2C9 | Your body clears this drug very slowly, so it can build up. A much lower starting dose, or a different drug, is suggested. | CPIC + CPIC Initiate therapy with 25 to 50% of the lowest recommended starting dose. Titrate dose upward to clinical effect or 25 to 50% of the maximum recommended dose with caution. In accordance with the prescribing information, use the lowest effective dosage for the shortest duration consistent with individual patient treatment goals. Upward dose titration should not occur until after steady-state is reached (at least 8 days for celecoxib and 5 days for ibuprofen, flurbiprofen, and lornoxicam after first dose in PMs). Carefully monitor adverse events such as blood pressure and kidney function during course of therapy. Alternatively, consider an alternate therapy not metabolized by CYP2C9 or not significantly impacted by CYP2C9 genetic variants in vivo. |
Moderate |
| IndeterminateCYP2C9 | The impact of your genotype on response to this drug is unknown. | CPIC Initiate therapy with recommended starting dose. |
Not rated |
| Not availableCYP2C9 | The impact of your genotype on response to this drug is unknown. | CPIC Initiate therapy with recommended starting dose. |
Not rated |
Source: CPIC
The gene behind the guidance
CYP2C9 Cytochrome P450 2C9
CYP2C9 metabolizes warfarin, phenytoin, celecoxib, and some NSAIDs. Variants that reduce its activity are most consequential for warfarin, where even small changes in drug clearance translate into very different doses (and a real bleeding risk if missed).
Poor metabolizers need substantially lower warfarin doses to hit the same INR target.
See all drugs affected by CYP2C9Browse the full drug class: Pain medications.
Related medications
Find out how your genetics affect Chlorpheniramine, ibuprofen and pseudoephedrine
Informational only, not medical advice. Pharmacogenetic guidance describes population-level patterns; your individual response depends on many factors. Never start, stop, or change a medication without talking to your prescribing clinician.