Myths vs facts: CYP2D6 and Schlaf

CYP2D6 is a drug-metabolizing enzyme that breaks down many medications – including antidepressants, antipsychotics, and opioids, which can indirectly affect sleep. However, a direct link between CYP2D6 variants and sleep quality or duration is not supported by robust human studies. Myths often claim that a CYP2D6 test reveals whether you are a 'morning person' or 'night owl' – that is false. Sleep-wake regulation is primarily governed by genes like PER, CLOCK, and CRY, not CYP2D6. A CYP2D6 test can be useful for adjusting medication dosages, but not for diagnosing or treating sleep issues. The evidence for a direct sleep effect is weak and largely marketing-driven. Consumers should not rely on such tests to explain sleep problems. For real sleep disorders, medical evaluation and sleep studies are appropriate.