Is Seroquel affected by genetics?
Yes. Its active ingredient has published pharmacogenetic guidance for a gene that varies between people.
Seroquel is affected by pharmacogenetics through the CYP3A4 gene. Your genotype for this gene can change how well Seroquel works for you or how well you tolerate it. The strongest evidence level on this page is Moderate, from the published guidelines shown below.
What's in Seroquel
Quetiapine Affected by CYP3A4
Affected by CYP3A4. Guidance from DPWG, moderate evidence.
Read the full quetiapine genetics guideQuetiapine phenotype recommendations
Published guidance from DPWG on how quetiapine should be dosed or substituted based on your CYP3A4 phenotype.
| Phenotype | What it means | Recommendation | Evidence |
|---|---|---|---|
| Normal MetabolizerCYP3A4 | Your CYP3A4 gene works normally, so the standard dose of this drug is used. | DPWG Use standard quetiapine dosing. |
Moderate |
| Intermediate MetabolizerCYP3A4 | Your body clears quetiapine slightly more slowly than average, but the effect is small and no dose change is needed. | DPWG No action is required. Use standard quetiapine dosing. |
Moderate |
| Poor MetabolizerCYP3A4 | Your body clears this drug slowly, so levels run much higher. For depression, another drug is often advised. Otherwise, a much lower dose is used. | DPWG Depression indication: choose an alternative agent (aripiprazole is less dependent on CYP3A4; olanzapine is not metabolised by CYP3A4). Other indications: use 30% of the normal quetiapine dose. |
Moderate |
| IndeterminateCYP3A4 | We couldn't read your CYP3A4 gene from your data, so we can't tailor advice for this drug. | DPWG Use standard quetiapine dosing and monitor response. |
Not rated |
| Not availableCYP3A4 | We do not have a CYP3A4 result for you, so we cannot personalize guidance for quetiapine. | DPWG Use standard quetiapine dosing and monitor response. |
Not rated |
Source: DPWG
The gene behind the guidance
CYP3A4 Cytochrome P450 3A4
CYP3A4 metabolizes more prescription drugs than any other enzyme. Somewhere around half of everything in the formulary passes through it. Most of the variation in CYP3A4 activity between people is driven by drug interactions and liver health rather than genetics, but a handful of variants (most notably CYP3A4*22) do meaningfully reduce enzyme output. Quetiapine is one of the drugs where the *22 effect is most clinically visible.
Reduced-function CYP3A4 carriers reach modestly higher plasma levels of CYP3A4 substrates. The effect is usually smaller than the equivalent CYP2D6 or CYP2C19 effect, but it stacks with concurrent CYP3A4 inhibitors.
See all drugs affected by CYP3A4Browse the full drug class: Antipsychotics.
Find out how your genetics affect Seroquel
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.