GlossaryCYP enzyme (CYP2D6 / CYP1A2)

CYP enzyme (CYP2D6 / CYP1A2)

Cytochrome P450 enzymes responsible for metabolising psilocin and many psychiatric medications in the liver. CYP2D6 is strongly inhibited by fluoxetine (Prozac) and paroxetine (Paxil), slowing their own clearance and potentially affecting psilocybin metabolism. CYP1A2 is strongly inhibited by fluvoxamine (Luvox), which may unpredictably increase psilocin blood levels — making that combination pharmacokinetically risky. Relevant when combining psilocybin with any psychiatric medication.

Full Explanation

CYP enzymes (CYP2D6 and CYP1A2) are cytochrome P450 enzymes responsible for metabolising psilocin and many psychiatric medications in the liver. CYP2D6 is strongly inhibited by fluoxetine (Prozac) and paroxetine (Paxil), slowing their own clearance and potentially affecting psilocybin metabolism. CYP1A2 is strongly inhibited by fluvoxamine (Luvox), which may unpredictably increase psilocin blood levels — making that combination pharmacokinetically risky. Relevant when combining psilocybin with any psychiatric medication.

See: Microdosing on SSRIs (/guides/microdosing-on-ssris).

Why It Matters

Understanding CYP enzymes is essential for anyone considering psilocybin while on SSRIs or other psychiatric medications — interactions can alter both drug levels and trip intensity.

Related Guides

Microdosing on SSRIs

Back to Glossary

Explore More Terms

Afterglow

The period of heightened mood, openness, and mental flexibility that commonly follows a full-dose psilocybin session — typically lasting 24 hours to several weeks. During the afterglow, neuroplasticity is elevated, default mode network activity is altered, and emotional and cognitive patterns are unusually open to change. Considered the critical integration window: therapeutic insights translate into lasting behavior change most effectively during this period. (Majić et al., 2015)

Spores

Reproductive cells produced by mushrooms, used to start new cultures and legal to possess in most US states.

Set and Setting

The combination of mindset (set) and environment (setting) that shapes a psychedelic experience.

Integration

The process of making meaning from a psychedelic experience and applying insights to daily life.

Microdosing

Taking sub-perceptual doses of psilocybin on a regular schedule for subtle cognitive and emotional benefits.

Psilocybin

A naturally occurring psychedelic compound found in certain mushrooms that produces altered states of consciousness.