Is Ketamine a Controlled Substance? Schedule III Status Explained

Yes — ketamine is a Schedule III controlled substance under the US Controlled Substances Act, as is its FDA-approved S-enantiomer esketamine (Spravato). Schedule III status places ketamine in the same broad regulatory category as codeine combination products, buprenorphine, and testosterone: recognized as having legitimate medical use, but subject to specific federal controls because of moderate dependence potential.

This page explains what Schedule III classification means in practice, how it shapes prescribing and dispensing, and how it affects access for patients pursuing ketamine therapy.

What the Controlled Substances Act Says

The Controlled Substances Act, passed in 1970, classifies regulated drugs into five schedules administered by the US Drug Enforcement Administration (DEA). The schedule reflects the substance's accepted medical use, abuse potential, and dependence liability.

Schedule III is defined as substances with: a currently accepted medical use in the United States; a potential for abuse less than that of Schedule I or II drugs; and abuse that may lead to moderate or low physical dependence or high psychological dependence.

Ketamine was originally placed on Schedule III in 1999, several decades after its 1970 FDA approval as an anesthetic. The scheduling decision reflected both growing recognition of recreational misuse and the desire to retain ketamine's legitimate medical role.

How the Five Schedules Compare

Schedule | Medical Use | Abuse Potential | Examples

Schedule I | None recognized | Highest | Heroin, LSD, MDMA, psilocybin

Schedule II | Yes (with strict controls) | High | Oxycodone, fentanyl, methylphenidate

Schedule III | Yes | Moderate to low | Ketamine, esketamine, buprenorphine, testosterone

Schedule IV | Yes | Lower | Alprazolam, lorazepam, zolpidem, tramadol

Schedule V | Yes | Lowest | Cough preparations with limited codeine

Schedule III sits in the middle. The lower schedule numbers carry stricter controls; the higher numbers are less restricted.

What Schedule III Means for Prescribers

Any clinician prescribing ketamine must hold a current DEA registration. Practical implications include:

• Prescriptions may be written, electronic, faxed, or — in limited situations — phoned in.
• A Schedule III prescription may be refilled up to five times within six months of the original issuance date, after which a new prescription is required.
• Prescriptions must include the prescriber's DEA number, patient identifying information, and other federally required elements.
• Dispensing pharmacies maintain controlled-substance records subject to DEA inspection.
• State prescription drug monitoring programs (PDMPs) typically require reporting of every dispensed prescription.

Compounding pharmacies that prepare custom sublingual or oral ketamine formulations operate under the same controlled-substance framework, with additional state-level compounding rules.

Implications for Patients

Access and Storage

Patients receiving take-home ketamine — typically as sublingual lozenges or troches via a telehealth or at-home program — are responsible for secure storage. Federal law makes diversion (sharing, selling, or transferring a controlled prescription) a criminal offense. Most clinics provide written instructions on storage, dose counts, and disposal of unused medication.

Telehealth Considerations

Telehealth prescribing of Schedule III ketamine has been permitted under DEA flexibilities established during the COVID-19 public health emergency, with the agency issuing successive extensions while finalizing permanent rules. Specific provisions around in-person evaluations and special registrations have continued to evolve. Patients using at-home ketamine programs should confirm that the prescribing model complies with current federal and state requirements.

Travel

Patients carrying ketamine prescriptions during travel should keep medications in original labeled containers and bring documentation of the prescription. International travel introduces additional complications: scheduling and legality vary across countries, and some jurisdictions treat ketamine as more strictly controlled than the US does.

Is Scheduling Likely to Change?

Scheduling decisions are made through formal rulemaking processes by the DEA in consultation with the FDA and the Department of Health and Human Services. Reclassification requires evidence-based review of abuse potential, dependence liability, and medical utility. Petitions to reschedule a substance can be filed, but the process typically takes years and involves public comment and scientific review.

As of the time of writing, there is no active rulemaking aimed at moving ketamine to a different schedule. Advocacy and research activity exists in both directions, with some arguing for tighter controls in light of growing at-home use and others arguing that ketamine's therapeutic profile supports broader access.

Common Misconceptions About Ketamine Scheduling

Several persistent misunderstandings show up in patient discussions about ketamine's controlled-substance status. Clarifying them helps set realistic expectations about access and risk.

"Schedule III means it has no medical use." This is incorrect. Schedule III explicitly requires that the substance have a currently accepted medical use. Schedule I is the category reserved for substances the DEA does not recognize as having accepted medical use.

"Ketamine therapy is legally gray." When prescribed by a licensed clinician with a DEA registration and dispensed through a legitimate channel, ketamine therapy is fully legal. Off-label use of an FDA-approved medication is a normal part of medical practice and not the same as illegal use.

"Esketamine is a different drug from ketamine, so the rules are different." Both racemic ketamine and esketamine are Schedule III. The distribution requirements differ — Spravato is restricted to certified REMS-registered sites — but the scheduling category is the same.

Safety and Final Considerations

Schedule III status is a regulatory designation, not a clinical contraindication. Whether ketamine is appropriate for a given patient depends on their psychiatric and medical history. Standard medical contraindications — including uncontrolled hypertension, recent cardiovascular events, active psychosis, untreated bipolar disorder, pregnancy, and severe liver disease — apply regardless of scheduling.

Patients pursuing legal ketamine treatment work with licensed clinicians and dispensing pharmacies who operate within the controlled-substance framework. Diversion or non-prescribed use carries serious legal as well as medical risks, including criminal penalties and the absence of any medical monitoring.