US federal law explainer

Controlled Substances Act: Psychedelics & Schedule I

The 1970 federal law that classifies psilocybin, MDMA, and LSD as having 'no accepted medical use' — and why Schedule I status is both the barrier and the target of US reform.

On this page

  1. What the Controlled Substances Act does
  2. The three Schedule I criteria
  3. When psychedelics were scheduled
  4. Schedule I vs. Schedule II: the medical-use line
  5. How rescheduling actually works
  6. Where rescheduling stands in 2026
  7. State laws vs. federal law
  8. Frequently asked questions

What the Controlled Substances Act does

The Controlled Substances Act is Title II of the Comprehensive Drug Abuse Prevention and Control Act of 1970 (Public Law 91-513), signed by President Nixon on October 27, 1970, and effective May 1, 1971.

It creates a single federal framework that regulates manufacturing, distribution, importing, and use of controlled substances. It divides those substances into five "schedules" based on medical use, abuse potential, and safety. Before the CSA, federal drug law was scattered across multiple statutes; the CSA unified them under one system enforced by the Drug Enforcement Administration (DEA).

Congress passed the CSA by voice vote — no recorded roll-call in either chamber. The lack of a recorded vote is a detail that rarely appears in summaries of the law, but it matters: it means no senator or representative is on record for or against the specific scheduling decisions made in 1970.

Why psychedelics ended up in Schedule I

Clinical research on LSD and psilocybin was active and promising through the late 1950s and 1960s. By 1966 the media and public debate had shifted sharply: recreational use spread, LSD was linked to dangerous behavior in press coverage, and political pressure to act grew fast. By the time Nixon signed the CSA in 1970, LSD, psilocybin, psilocin, mescaline, and DMT were placed in Schedule I, cutting off almost all further US research for decades.

The three Schedule I criteria

A substance lands in Schedule I when it meets all three criteria under 21 U.S.C. § 812(b)(1): high abuse potential, no currently accepted medical use in the US, and a lack of accepted safety for use under medical supervision.

All three must be true at the same time. A substance with a high abuse potential but a recognized medical use goes into Schedule II, not Schedule I. The "no accepted medical use" standard is set by the FDA based on whether there is substantial evidence of effectiveness from adequate and well-controlled studies — the same bar required for drug approval.

The research catch-22. To demonstrate accepted medical use, researchers need large clinical trials. But Schedule I status makes getting DEA research registrations slow and expensive, limits the supply of research-grade material, and blocks most institutional research sites. The schedule creates a barrier to the very evidence that could change it. DEA's 2026 aggregate production quota of 50,000 grams of psilocybin for research — up from 30,000 grams in 2025 — signals some easing of that barrier.

When psychedelics were scheduled

Most classic psychedelics were placed in Schedule I when the CSA took effect in 1971, having already been banned from interstate commerce under earlier drug laws. MDMA was not in the original list; it was added by emergency action in 1985.

For a fuller picture of how individual substances are treated in different legal systems, see our guides on psilocybin, MDMA-assisted therapy, LSD, DMT, and ibogaine.

Schedule I vs. Schedule II: the medical-use line

The gap between Schedule I and Schedule II is the single most consequential line in the CSA for psychedelic medicine — and it comes down to three words: accepted medical use.

Schedule II drugs like fentanyl, oxycodone, methamphetamine, and even cocaine have very high abuse potential, but they have an accepted medical use. That means a licensed doctor can write a prescription, a pharmacist can fill it, and a patient can use it under supervision. Schedule I drugs have none of that pathway. They cannot be prescribed under any circumstances.

Moving psilocybin, for example, from Schedule I to Schedule II would not legalize it for general use. It would allow a licensed physician to prescribe an FDA-approved psilocybin product, under tight DEA reporting requirements, in the same way a doctor prescribes oxycodone. That is the distinction the COMPASS Pathways NDA filing targets for 2026–2027.

Feature Schedule I Schedule II
Accepted medical use None Yes, even if with severe restrictions
Can a doctor prescribe it? No Yes, with DEA registration
Can a pharmacy dispense it? No Yes, under strict controls
Research authorization DEA Schedule I researcher registration required; very limited supply DEA registration required; larger manufacturer pool
Examples Psilocybin, LSD, MDMA, DMT, mescaline, ibogaine Fentanyl, oxycodone, cocaine (topical), methamphetamine (Desoxyn)
If FDA approves a formulation Approved formulation moves to appropriate schedule; substance itself may stay I N/A — already has medical use

Important nuance: FDA approval of a specific drug product does not automatically reschedule the raw substance. When Marinol (synthetic THC) was approved, it was placed in Schedule II while cannabis stayed in Schedule I. A psilocybin drug approval would likely follow the same path — the approved product moves; raw psilocybin mushrooms stay Schedule I. For the current legal landscape by state, see our legal status by state tool.

How rescheduling actually works

Rescheduling a controlled substance requires one of three paths: a DEA-initiated rulemaking, a petition filed by any interested party, or direct congressional legislation.

The petition path (most common)

Any person can file a petition with the DEA to add, remove, or transfer a substance between schedules. DEA must then forward the petition to the Department of Health and Human Services (HHS) for a scientific and medical evaluation by FDA. That is step one, and it alone can take years under a pending docket.

FDA sends a scheduling recommendation back to DEA. DEA is not required to follow the recommendation — as the MDMA case in 1988 showed — but it is legally bound by the scientific finding on medical use if HHS finds one. DEA then opens a formal Notice of Proposed Rulemaking (NPRM), accepts public comment (usually 30–60 days), and issues a final rule.

If a substance is already pending an NDA approval at FDA, the timeline compresses. Once FDA approves a New Drug Application, DEA is required to issue an interim scheduling rule within 90 days. That is the fast path that COMPASS Pathways and other sponsors are working toward for psilocybin.

The congressional path

Congress can reschedule a drug by passing a bill, as it did with anabolic steroids in 1990. No bill to reschedule any psychedelic has passed both chambers as of June 2026, though proposals have been introduced. The psychedelic legalization tracker shows current bill status in real time.

Decriminalization is not rescheduling. A city or state can stop arresting people for possession — that is decriminalization. It does not change the CSA. Federal law still applies on federal land (national parks, federal buildings, VA hospitals, airports), and the Schedule I status still blocks prescriptions and insurance coverage everywhere, even in Oregon and Colorado.

Where rescheduling stands in 2026

No Schedule I psychedelic has been rescheduled as of June 2026, but multiple federal actions have moved the needle closer than at any point since 1970.

Psilocybin

In August 2025, the DEA forwarded a psilocybin rescheduling petition — filed by Dr. Sunil Aggarwal of the Advanced Integrative Medical Science Institute — to HHS for scientific review. HHS has not announced a timeline. Separately, COMPASS Pathways reported positive results in two consecutive Phase 3 trials for treatment-resistant depression (COMP005 in June 2025 and COMP006 in February 2026) and is targeting a rolling NDA submission in Q4 2026. If the NDA is approved, DEA must issue an interim scheduling rule within 90 days — the fastest rescheduling route available.

MDMA

The FDA rejected Lykos Therapeutics' NDA for MDMA-assisted therapy for PTSD in August 2024, citing insufficient evidence of efficacy and concerns about trial blinding. MDMA remains Schedule I. A new clinical program would need to run additional trials before another NDA is filed.

Trump executive order (April 2026)

President Trump signed an executive order in April 2026 directing FDA to issue Commissioner's National Priority Vouchers to psychedelic therapies with Breakthrough Therapy designation. These vouchers can compress FDA review from months to weeks. The order also allocates $50 million through ARPA-H to match state psychedelic research investments and directs HHS and VA to expand clinical trial access for veterans. The order does not reschedule any substance. For the full policy breakdown, see our guide to the Trump psychedelics executive order.

LSD, DMT, mescaline, ibogaine

No active rescheduling petitions or NDA filings are pending for these substances at the federal level as of June 2026. Research programs exist, but none has reached the NDA stage. At the state level, Colorado's Proposition 122 decriminalized DMT, ibogaine, and mescaline for personal use — but that does not affect their federal Schedule I status. For substance-specific guides, see ayahuasca and DMT, ibogaine, and mescaline and peyote.

State laws vs. federal law

State decriminalization and regulated access programs operate in tension with the CSA, not in place of it. When Oregon's Measure 109 or Colorado's Proposition 122 create legal psilocybin programs, they remove state criminal penalties — they cannot remove federal ones.

In practice, the federal government has not prosecuted people participating in state-licensed psilocybin programs. But Schedule I status creates three real-world limits that state law cannot fix: no health insurance coverage (insurers follow federal classification), no VA-covered treatment for veterans, and no use at federal facilities or on federal land.

This is why cost is the biggest barrier to access even in states with legal programs. A supervised psilocybin session in Oregon or Colorado typically costs $1,000 to $3,000 out of pocket. Schedule I prevents the insurance billing codes that would make it reimbursable. For a state-by-state view of what is and is not legal today, use the full US legal status guide or the interactive state tool.

For city-level policies that have gone further than most states, see our guide to US cities that decriminalized psilocybin. For an overview of where mushrooms specifically stand, see are magic mushrooms legal?

Frequently asked questions

Are psilocybin and LSD still Schedule I in 2026?

Yes. Psilocybin, LSD, DMT, mescaline, ibogaine, and MDMA all remain Schedule I under the federal Controlled Substances Act as of June 2026. No rescheduling action has been finalized for any of these substances. Oregon and Colorado have created state-level access programs, but federal law has not changed.

What does Schedule I mean for a drug?

Schedule I means three things under 21 U.S.C. § 812: the substance has a high potential for abuse, it has no currently accepted medical use in the United States, and it lacks accepted safety for use under medical supervision. Schedule I drugs cannot be prescribed by a doctor and are banned from pharmacy dispensing entirely.

How would psilocybin get rescheduled?

Rescheduling requires a petition to the DEA, which must forward it to HHS and FDA for a scientific evaluation. FDA sends a scheduling recommendation back to DEA. DEA then opens a formal rulemaking process with a public comment period before issuing a final rule. If FDA approves a psilocybin drug product first, DEA must issue an interim scheduling rule within 90 days — the fastest path. Congress can also reschedule by passing legislation.

When was MDMA made Schedule I?

The DEA emergency-scheduled MDMA as Schedule I on May 31, 1985 — the first time DEA had ever used its emergency scheduling authority. A federal administrative law judge later recommended Schedule III, but the DEA administrator overruled that in 1988 and permanently kept MDMA at Schedule I, where it remains today.

What is the difference between Schedule I and Schedule II?

The key difference is accepted medical use. Schedule II drugs such as fentanyl, oxycodone, and cocaine have a recognized medical use in the US and can be prescribed, even though their abuse potential is high. Schedule I drugs have no accepted medical use at all and cannot be prescribed by any doctor in any circumstance. Moving a substance from Schedule I to Schedule II would allow physicians to prescribe an FDA-approved version of it.

Does Trump's 2026 executive order change federal Schedule I for psychedelics?

No. President Trump's April 2026 executive order directs FDA to fast-track psychedelic therapies with Breakthrough Therapy designation and allocates $50 million through ARPA-H for psychedelic research. It does not reschedule any substance. Psilocybin, MDMA, LSD, DMT, mescaline, and ibogaine are still Schedule I federally unless a formal rulemaking or congressional act changes that.

Want to track when the schedule changes?

Our legalization tracker follows active rescheduling petitions, NDA filings, and state bills in real time — updated as DEA and FDA act.

Psychedelic legalization tracker  ·  Legal status by state

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Sources

  1. 91st United States Congress. Comprehensive Drug Abuse Prevention and Control Act of 1970, Title II (Controlled Substances Act) — Public Law 91-513. GovInfo.gov, 1970. Full statute text.
  2. U.S. House of Representatives, Office of the Law Revision Counsel. 21 U.S. Code § 812 — Schedules of controlled substances. uscode.house.gov, 2024. Current statute text.
  3. Drug Enforcement Administration. Schedules of Controlled Substances: Temporary Placement of MDMA into Schedule I — Federal Register Vol. 50, No. 105 (May 31, 1985). Federal Register / Wikimedia Commons, 1985. Federal Register notice.
  4. Drug Enforcement Administration. Schedules of Controlled Substances: Rescheduling of Marijuana — NPRM (May 2024). DEA.gov, 2024. DEA NPRM (rescheduling process reference).
  5. The White House. Accelerating Medical Treatments for Serious Mental Illness — Executive Order (April 2026). whitehouse.gov, 2026. Executive order text.