Is Seroquel affected by genetics?

Yes — the active ingredient is metabolized by a gene known to vary between individuals.

Relevant genes: CYP3A4

Seroquel is affected by pharmacogenetics through the CYP3A4 gene. Your genotype for this gene can change how your body processes Seroquel, which can affect both how well it works and how well you tolerate it. The strongest evidence level on this page is Moderate, based on CPIC or FDA guidelines.

What's in Seroquel

quetiapine affected by CYP3A4

Affected by CYP3A4 · DPWG · Moderate evidence

Read the full quetiapine genetics guide →

Quetiapine 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 Metabolizer CYP3A4	Your CYP3A4 activity is typical; standard quetiapine dosing applies.	DPWG Use standard quetiapine dosing.	Moderate
Intermediate Metabolizer CYP3A4	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 Metabolizer CYP3A4	Your body clears quetiapine slowly, which substantially raises its concentration in your blood. For depression, a different medication is typically recommended. For other indications, a much lower dose is typically 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
Indeterminate CYP3A4	We were not able to determine your CYP3A4 metabolism status, so we cannot personalize guidance for quetiapine.	DPWG Use standard quetiapine dosing and monitor response.	—
Not available CYP3A4	We do not have a CYP3A4 result for you, so we cannot personalize guidance for quetiapine.	DPWG Use standard quetiapine dosing and monitor response.	—

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 CYP3A4 →

Browse the full drug-class: Antipsychotics.

Find out how your genetics affect Seroquel

This page describes the general pharmacogenetics. A Gene2Rx report analyzes your own DNA to tell you which metabolizer group you fall into, across every medication.

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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.