Schedule III

Schedule III is a tier within the United States Controlled Substances Act (CSA) of 1970, designating substances that have a currently accepted medical use and whose abuse potential is judged lower than that of Schedules I or II. The statute describes the tier as involving moderate to low potential for physical dependence.

The CSA is administered jointly by the Drug Enforcement Administration (DEA) and the Food and Drug Administration (FDA), which apply a multi-factor test when assigning or reviewing a substance's placement. The phrase currently accepted medical use is a legal term with a specific procedural definition — not a direct reading of the clinical literature — and its scope has been contested in court.

What it means in practice

Placement in Schedule III allows a clinician to prescribe the substance with up to five refills within six months of the original prescription — a flexibility not available under Schedule II, which prohibits refills. Prescriptions may be issued orally or electronically, not only in writing.

A substance enters Schedule III through an act of Congress or through administrative rulemaking by the DEA, which involves a public-comment period and a formal record. The DEA may also issue a temporary emergency placement when it finds an imminent hazard, bypassing the usual timeline.

Substances placed here include certain anabolic steroids, ketamine, and buprenorphine. The classification extends to preparations and formulations of the base substance; specific low-concentration preparations may be exempted from control by separate regulation.

How jurisdictions vary

The number carries no fixed meaning across borders. In the United Kingdom, Schedule 3 refers to a tier under the Misuse of Drugs Regulations 2001 — a different legal instrument, enacted under different criteria, covering different substances. A drug that is Schedule III in the United States may be unscheduled, more tightly restricted, or placed in an entirely different tier in the UK, Canada, or Australia.

At the international level, the United Nations drug treaties — the 1961 Single Convention on Narcotic Drugs and the 1971 Convention on Psychotropic Substances — each use their own four-schedule systems. Their placements and criteria do not correspond to US schedule numbers.

What is contested

The statutory phrase currently accepted medical use has a procedural definition in US law that has not always tracked the published scientific record. Courts and the DEA have applied it by administrative criteria — such as FDA marketing approval — rather than by direct reference to clinical evidence.

The most documented instance involves cannabis, which remained in Schedule I for decades despite accumulating research. In 2024 the DEA proposed moving it to Schedule III following an FDA medical-use finding. As of this entry's date, that proposal had not been finalised — illustrating that rescheduling turns on administrative and political processes as well as the evidence base.

Scope and currency

This entry describes Schedule III as defined under the United States Controlled Substances Act and is not legal advice. It does not state the law where the reader is located, and does not account for state, territorial, or foreign law.

This entry states the position as of August 2026. Drug schedules change through legislation and administrative rulemaking; official sources should be consulted for current status. Each substance page on Psychedex includes a legal status section with its own jurisdiction, date, and source — that is the record to rely on for any specific compound.