CYP2D6
cytochrome P450 family 2 subfamily D member 6 (gene/pseudogene)
Gene summary
A protein-coding gene on chromosome 22 (drug metabolism (phase i)). Encodes a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and other lipids.
Source: NCBI Gene, accessed 2026-10-07.
Protein reference (UniProt)
- Protein
Cytochrome P450 2D6
- Function (excerpt)
A cytochrome P450 monooxygenase involved in the metabolism of fatty acids, steroids and retinoids. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate, and reducing the second into a water molecule, with two electrons provided by NADPH via cytochrome P450 reductase (NADPH--hemoprotein reductase). Catalyzes the epoxidation of double bonds of polyunsaturated fatty acids (PUFA). Metabolizes endocannabinoid arachidonoylethanolamide (anandamide) to 20-hydroxyeicosatetraenoic acid ethanolamide (20-HETE-EA) and 8,9-, 11,12-, and 14,15-epoxyeicosatrienoic acid ethanolamides (EpETrE-EAs), potentially modulating endocannabinoid system signaling. Catalyzes the hydroxylation of carbon-hydrogen bonds. Metabolizes cholesterol toward 25-hydroxycholesterol, a physiological regulator of cellular cholesterol homeostasis. Catalyzes the oxidative transformations of all-trans retinol to all-trans retinal, a precursor for the active form all-trans-retinoic acid.
- Pathway
Cofactor metabolism; retinol metabolism. Lipid metabolism; fatty acid metabolism. Steroid metabolism; cholesterol metabolism.
- Subcellular location
Endoplasmic reticulum membrane; Microsome membrane.
Source: UniProtKB/Swiss-Prot P10635, release 2026_03, licensed CC BY 4.0. This is the protein’s normal biology, not evidence about post-drug syndromes; associated conditions are inherited disorders of the gene, not PFS, PSSD or PRSD.
Why its pathway is in the library
Phase I enzymes determine exposure to finasteride, SSRIs, and other implicated drugs; variation here shapes the likelihood and persistence of adverse effects.
Written for the whole drug metabolism family, not for CYP2D6 specifically.
Mentioned in 6 corpus records
- Powers · Reddit commentCurated Powers pick
Re: Can you stop Hairloss effectively without risking PFS?
u/drwillpowers · r/DrWillPowers
Powers offered a thought experiment: if a PFS-susceptible man were chemically castrated, given dutasteride for two months, withdrawn, then "uncastrated," he would never develop PFS if the theory is correct — because it is about metabolite load, not just the…
CYP2D6CYP3A4LRP2PRH-03302026-07-30T04:02:01ZPFSPSSDPowers Reddit history - Powers · Reddit commentCurated Powers pick
Pharmacogenomic exposure amplification: a standard SSRI dose can feel like 3–4× in slow metabolizers
u/drwillpowers · r/DrWillPowers
Replying to a commenter flagging CYP2D6 slow-metabolizer variants surfacing in community-read PSSD genomes, Powers describes a genetic variant that amplifies SSRI exposure — a standard dose can feel like three to four times the dose — and notes the same gene…
CYP2D6PRH-15082026-06-07T22:45:26ZPSSDPowers Reddit history - Peer-reviewed paper
Influence of CYP2C19, CYP2D6, and ABCB1 Gene Variants and Serum Levels of Escitalopram and Aripiprazole on Treatment-Emergent Sexual Dysfunction: A Canadian Biomarker Integration Network in Depression 1 (CAN-BIND 1) Study
Farhana Islam, Leen Magarbeh, Samar S. M. Elsheikh, Stefan M. Kloiber, Caroline Wanderley Espinola, Venkat Bhat, Benicio Noronha Frey… · The Canadian Journal of Psychiatry
In 178 adults with major depressive disorder treated with escitalopram (weeks 0-8), nonresponders were augmented with aripiprazole while responders continued escitalopram alone (weeks 8-16), with sexual function and satisfaction tracked on the SexFX scale…
ABCB1CYP2C19CYP2D6MECH-0352023 (epub Oct 2023)PSSDSystems review · Oct 2026 - Peer-reviewed paperPSSD Discord pickRetracted — do not cite
CYP2D6 Is Inducible by Endogenous and Exogenous Corticosteroids
Muhammad Farooq, Edward J Kelly, Jashvant D Unadkat · Drug Metabolism and Disposition
The authors challenged the dogma that CYP2D6 is non-inducible, showing that in sandwich-cultured human hepatocytes CYP2D6 mRNA, protein, and activity were robustly (>10-fold) induced by endogenous (cortisol, corticosterone) and exogenous (dexamethasone…
CYP2D6DISC-0242016PSSDPSSD Discord picks - Peer-reviewed paperPSSD Discord pick
Potential role of CYP2D6 in the central nervous system
Cheng J, Zhen Y, Miksys S, Beyoğlu D, Krausz KW, Tyndale RF, Yu A, Idle JR, Gonzalez FJ · Xenobiotica
Mouse study using a transgenic human-CYP2D6 model, finding that human CYP2D6 is expressed not only in liver but also in brain, where it altered serotonin and metabolite levels plus broader brain metabolomic profiles, and shifted anxiety-related behavior. The…
CYP2D6DISC-0052013PSSDPSSD Discord picks - Peer-reviewed paperPSSD Discord pick
CYP2D in the brain
Yoshihiko Funae, Wataru Kishimoto, Toshio Cho, Toshiro Niwa, Toyoko Hiroi · Drug Metabolism and Pharmacokinetics
This review surveys CYP2D isoforms in the brain: in rats CYP2D4 mRNA is most abundant in cerebellum, striatum, pons and medulla, while in humans only CYP2D6 is expressed, highest in cerebellum. It reports that CYP2D enzymes metabolize both xenobiotics…
CYP2D6DISC-0232003PFSPSSDPSSD Discord picks
Also in drug metabolism (phase i)
All 23 genes- COMT
catechol-O-methyltransferase
chr 22· Drug metabolism· 4 records - CYP3A4
cytochrome P450 family 3 subfamily A member 4
chr 7· Drug metabolism· 2 records - CYP2C19
cytochrome P450 family 2 subfamily C member 19
chr 10· Drug metabolism· 1 record - CYP3A5
cytochrome P450 family 3 subfamily A member 5
chr 7· Drug metabolism· 1 record - MAOA
monoamine oxidase A
chr X· Drug metabolism· 1 record - AKR1B1
aldo-keto reductase family 1 member B
chr 7· Drug metabolism· Pathway candidate - AKR1B10
aldo-keto reductase family 1 member B10
chr 7· Drug metabolism· Pathway candidate - ALDH1A1
aldehyde dehydrogenase 1 family member A1
chr 9· Drug metabolism· Pathway candidate
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