Compound explainer

4-AcO-DMT: Legal Status, Effects, and Safety (2026)

4-AcO-DMT (psilacetin) is a psilocybin prodrug not explicitly scheduled — but the Federal Analogue Act treats it as Schedule I when intended for human use.

On this page

  1. What is 4-AcO-DMT?
  2. Is 4-AcO-DMT legal? Federal and state law
  3. The Federal Analogue Act, explained
  4. Effects, dose, and duration
  5. 4-AcO-DMT vs psilocybin: a comparison
  6. Safety profile and risks
  7. Frequently asked questions

What is 4-AcO-DMT?

4-AcO-DMT is a synthetic tryptamine. The full chemical name is 4-acetoxy-N,N-dimethyltryptamine. Common nicknames include psilacetin and O-acetylpsilocin.

The compound was first synthesized by Albert Hofmann and Franz Troxler at Sandoz in 1963. It is a prodrug, meaning the body converts it into another active compound. In this case, the body removes the acetyl group and produces psilocin.

Psilocin is the same molecule that produces the trip when you eat psilocybin mushrooms. Mushroom psilocybin is also a prodrug — the body removes a phosphate group from psilocybin and turns it into psilocin. Both pathways end at the same active compound.

Why people use 4-AcO-DMT

Two main reasons people search out 4-AcO-DMT:

  1. Dose precision. Synthetic 4-AcO-DMT can be weighed to the milligram. Mushroom potency varies widely between flushes and species.
  2. Less body load. Users report less nausea and gut discomfort than with whole mushrooms. The mushroom matrix (chitin, other compounds) is missing.

Functionally no. 4-AcO-DMT is not on the federal Schedule I list. But the Federal Analogue Act and several state laws still treat it as Schedule I when sold or possessed for human consumption.

Federal law

The DEA has not formally scheduled 4-AcO-DMT. There is no specific entry for it in 21 CFR §1308. So under a literal reading of the Controlled Substances Act, the compound is "unscheduled."

However, the Federal Analogue Act treats any drug "substantially similar" to a Schedule I or II controlled substance as Schedule I when intended for human consumption. The DOJ has argued that 4-AcO-DMT is an analogue of psilocin, which is itself Schedule I. Federal prosecutions under this theory have occurred.

State law

State laws vary. Three states explicitly schedule 4-AcO-DMT:

Other states (including New York and California) treat 4-AcO-DMT as an analogue under their own analogue acts. Texas, Michigan, and Maryland have all prosecuted 4-AcO-DMT cases under state analogue statutes.

Treat 4-AcO-DMT as carrying real legal risk. The "not for human consumption" label on research-chemical vendor sites is not a magic shield. If federal or state prosecutors find evidence of intended human use — packaging, dosing scales, online order history — the analogue acts apply.

The Federal Analogue Act, explained

The Federal Analogue Act is part of the Controlled Substances Act, codified at 21 U.S.C. § 813. Congress added it in 1986 to address designer drugs that mimicked Schedule I compounds but were not explicitly scheduled.

The Act treats any chemical that meets all three of these tests as if it were Schedule I:

  1. Chemical structure "substantially similar" to a Schedule I or II drug.
  2. Pharmacological effect "substantially similar" to a Schedule I or II drug, or the user/seller represents that it has that effect.
  3. The substance is intended for human consumption.

4-AcO-DMT fits all three when sold for use. Its structure is one acetyl group different from psilocin. Its effect is psilocin once metabolized. And vendors usually describe it as a psychedelic.

Effects, dose, and duration

Parameter 4-AcO-DMT (oral)
Threshold dose~5 mg
Common dose15–25 mg
Strong dose25–40 mg
Onset20–40 minutes
Peak1–3 hours
Total duration4–6 hours
Mechanism5-HT2A partial agonist (after conversion to psilocin)

These figures are based on user reports and pharmacology reviews, not clinical trial data. Individual response varies. The effect profile resembles a classical psilocybin trip.

4-AcO-DMT vs psilocybin: a comparison

Factor 4-AcO-DMT Psilocybin (mushrooms)
Active metabolite Psilocin (after deacetylation) Psilocin (after dephosphorylation)
Federal legal status Unscheduled by name; Federal Analogue Act applies Schedule I
Dose precision High (synthetic powder) Low (mushroom potency varies)
Onset 20–40 min 30–60 min
Duration 4–6 hours 4–6 hours
Nausea / body load Reportedly less Common in first hour
FDA trials None active Multiple Phase 3 (Compass, Usona, Filament)
Supply chain Research chemical vendors (gray market) Mushrooms (illegal) or licensed OR/CO/NM

Safety profile and risks

Once 4-AcO-DMT converts to psilocin, the safety profile is basically the same as psilocybin. The bigger 4-AcO-DMT-specific risks are around purity, dosing accuracy, and legal exposure.

Pharmacological risks

Supply chain risks

4-AcO-DMT sold by research-chemical vendors is not third-party tested in any standardized way. Past gray-market 4-AcO-DMT batches have included misidentified analogues (4-HO-MET, 5-MeO-MiPT) and contamination. This is one reason synthetic psilocybin (Compass COMP360, Usona) carries lower clinical risk than gray-market 4-AcO-DMT.

Legal risk

Federal felony exposure under the Analogue Act is real. State analogue acts add additional charges in some jurisdictions. Florida, Georgia, and Louisiana name 4-AcO-DMT specifically.

The bottom line

4-AcO-DMT is a synthetic psilocin prodrug with effects similar to psilocybin mushrooms. The legal landscape is messier than the pharmacology — it is not federally scheduled by name, but the Federal Analogue Act treats it as Schedule I when intended for use.

If you are looking for legal psilocybin access in 2026, the practical options are Oregon's Measure 109 service centers, Colorado's Prop 122 healing centers, and (as of April 2025) New Mexico's medical psilocybin program. None of these use 4-AcO-DMT — they use psilocybin extracted from Psilocybe cubensis or synthesized for clinical use.

Frequently asked questions

Is 4-AcO-DMT legal in the United States?

No, in practice. 4-AcO-DMT (4-acetoxy-N,N-dimethyltryptamine, also called psilacetin) is not explicitly listed on the federal Schedule I list. However, the Federal Analogue Act (21 U.S.C. § 813) treats substances 'substantially similar' to Schedule I drugs as Schedule I when intended for human consumption. DOJ has prosecuted 4-AcO-DMT cases as a psilocin analogue. Several states (Florida, Georgia, Louisiana) explicitly schedule it.

How is 4-AcO-DMT different from psilocybin?

4-AcO-DMT and psilocybin are both prodrugs of psilocin, which is the molecule that crosses the blood-brain barrier and produces psychedelic effects. The body removes a phosphate group from psilocybin to make psilocin; it removes an acetate group from 4-AcO-DMT to make the same psilocin. Subjective effects are very similar to a mushroom trip, though many users report a faster onset with 4-AcO-DMT.

What is the Federal Analogue Act and does it apply to 4-AcO-DMT?

The Federal Analogue Act (21 U.S.C. § 813) treats any substance 'substantially similar' in chemical structure or pharmacological effect to a Schedule I or II controlled substance as Schedule I — but only when intended for human consumption. DOJ has argued that 4-AcO-DMT is substantially similar to psilocin (which is Schedule I). Federal prosecutions under this theory have occurred. The 'not for human consumption' label on research-chemical vendor sites does not provide legal protection when there is evidence of intended use.

Which states explicitly schedule 4-AcO-DMT?

At least three states have explicitly scheduled 4-AcO-DMT or named it in tryptamine bans: Florida (scheduled under Fla. Stat. §893.03), Georgia (under O.C.G.A. §16-13-25), and Louisiana (under La. R.S. §40:964). Other states (New York, California) treat it as an analogue under state analogue acts. Treat 4-AcO-DMT as carrying meaningful federal and state criminal risk regardless of explicit scheduling.

Is 4-AcO-DMT being studied for FDA approval?

No active FDA-registered trials use 4-AcO-DMT as the study drug. Mainstream psilocybin drug development uses synthetic psilocybin (Compass Pathways COMP360, Usona, and Filament Health botanical psilocybin). 4-AcO-DMT exists primarily in the research-chemical and gray market, with no significant clinical research program.

Is 4-AcO-DMT safer than psilocybin mushrooms?

Not meaningfully. Because 4-AcO-DMT converts to psilocin in the body, the safety profile is similar to psilocybin mushrooms once converted. Synthetic 4-AcO-DMT does allow precise dosing, while mushroom potency varies. The bigger safety concern is purity — vendor product is not third-party tested for misidentification or contamination, and law enforcement risk is real.

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Sources

  1. Wikipedia contributors. 4-AcO-DMT. Wikipedia, 2026. Wikipedia.
  2. Psychedelic Science Review. The State of the Art of Psilacetin (4-AcO-DMT). PSR, 2020. PSR.
  3. US Congress. Federal Analogue Act, 21 U.S.C. § 813. Cornell Legal Information Institute, 1986. Cornell LII.
  4. Florida Legislature. Fla. Stat. §893.03 — Schedule I including 4-acetoxy-DMT. Florida Statutes, 2024. Florida.
  5. Georgia General Assembly. O.C.G.A. §16-13-25 — Schedule I controlled substances. Georgia Code, 2023. Georgia.