Posaconazole

A triazole antifungal, FDA-approved to treat invasive aspergillosis, prevent Aspergillus and Candida infections in severely immunocompromised people, and treat oropharyngeal candidiasis.

psilodex.org/m/posaconazole · data v2026.10.05

Clinical contraindication: None listed; No label contraindication covering psilocybin was found. This is not a finding that the combination has been shown to be without risk.
Psilocybin evidence: No psilocybin data
Half-life: ~26–35 h; Approximate, in adults. Source under Interaction below.

Named in state rules?

Not namedColorado Condition rules (3)

Not namedOregon

PendingNew Mexico

Cite asPsilodex, “Posaconazole”, v2026.10.05. psilodex.org/m/posaconazole

Clinical data and state rules are separate facts. Both are shown; neither is a decision.

What it is used for

FDA status

FDA-approved

FDA-approved for

Invasive aspergillosis (treatment)
Prevention of invasive Aspergillus and Candida infections in severely immunocompromised people
Oropharyngeal candidiasis (oral suspension)

Sources [1]

01 Interaction with psilocybin

Not studied with psilocybin; it slows an enzyme that helps break down psilocybin, so higher levels are possible. Also, it can cause heart-rhythm (QT) effects.

Detail Posaconazole is a strong CYP3A4 inhibitor (blocks a liver enzyme). CYP3A4 metabolized psilocin (psilocybin's active form) in lab studies (Thomann 2024), so posaconazole may raise psilocin levels. However, the body clears psilocin mainly by glucuronidation and conversion to 4-HIAA. The body also clears posaconazole itself mainly by glucuronidation (UGT). No psilocybin data exist. Psilocybin transiently raises heart rate and blood pressure. Also, posaconazole is associated with QT prolongation and torsades de pointes (dangerous heart-rhythm changes). Sources [1][2]

Human data with psilocybin: No psilocybin data; based on how it works and its label
Half-life: ~26–35 h (formulation-dependent) (FDA label, checked 2026-10-04) Delayed-release tablet 26–31 h; injection 27 h; oral suspension 35 h (range 20–66 h).

Evidence types on this record

No psilocybin dataNo psilocybin data: no human data with psilocybin or another classic psychedelic; the text draws on the medication's own pharmacology and its label or reference facts

02 Pharmacology relevant to psilocybin

2 listed · counted on reports

Liver injury: The label or source warns of liver injury, from raised liver enzymes to liver failure. Liver disease also affects how the body clears psilocin. Sources [1]
QT-prolonging: Lengthens the QT interval on an ECG, a measure of the heart’s electrical recovery between beats. A long QT raises the risk of a dangerous heart rhythm, more so with other QT-prolonging drugs or low potassium or magnesium. Sources [1]

03 State rules

Plain-language summary · official text governs

CO4 CCR 755-1

Not namedCondition rules (3)

No provision names this medication or its class.

Colorado · checked 2026-10-04

OROAR 333-333

Not named

No provision names this medication or its class.

Oregon · checked 2026-10-04

NM7.35.3 NMAC (proposed)

Pending

New Mexico's clinical rules (proposed 7.35.3 NMAC) are not final. No provision naming this medication has been found.

New Mexico · checked 2026-10-04

04 Conditions to ask about

Screening items in state rules

This medication is usually taken for a condition. State rules screen for some conditions directly, so the medication is a prompt to ask about them. Confirm with the participant; never assume a condition from the medication.

Organ transplant (severe chronic illness)
- CO 2.5(A)(2) · Clinical Facilitator licensees
- CO 6.16(F)(2)(a) · Facilitators without a clinical facilitator license
- CO 6.16(F)(1) · All licensees

05 Sources

NOXAFIL (posaconazole) injection, delayed-release tablets, oral suspension, PowderMix (Merck) · FDA label (DailyMed) — revised 2026-03 | QT-prolonging: 5.2 Arrhythmias and QT Prolongation "Some azoles, including Noxafil, have been associated with prolongation of the QT interval on the electrocardiogram. In addition, cases of torsades de pointes have been reported in patients taking Noxafil." | Liver injury: 5.5 Hepatic Toxicity "Cases of more severe hepatic reactions including cholestasis or hepatic failure including deaths have been reported in patients with serious underlying medical conditions" | "Posaconazole is a strong CYP3A4 inhibitor." "Posaconazole is primarily metabolized via UDP-glucuronosyltransferase and is a substrate of p-glycoprotein (P-gp) efflux." | 12.3 "Noxafil delayed-release tablet is eliminated with a mean half-life (t½) ranging between 26 to 31 hours." "Noxafil oral suspension is eliminated with a mean half-life (t½) of 35 hours (range: 20-66 hours)."
Thomann J, Kolaczynska KE, Stoeckmann OV, et al. In vitro and in vivo metabolism of psilocybin’s active metabolite psilocin. Front Pharmacol 2024;15:1391689. — Abstract: "recombinant CYP2D6 and CYP3A4 enzymes metabolized nearly 100% and 40% of psilocin, respectively." "MAO-A transformed psilocin into minimal amounts of 4-HIAA and 4-HTP." "In conclusion, MAO-A, CYP2D6, and CYP3A4 are involved in psilocin's metabolism." Introduction: "Around 33% of a psilocybin dose is renally excreted as 4-HIAA."

Record history

v2026.10.02First published.
2026-10-04Last reviewed against its sources.

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