Schedule IV

Schedule IV is a tier in the United States Controlled Substances Act (CSA) of 1970, designating substances that have a currently accepted medical use and are judged to carry a lower potential for abuse than substances in Schedule III. The classification is a regulatory ranking created by federal law, not a clinical safety assessment. Most benzodiazepines and several hypnotic and sedative medications sit here.

The same phrase, Schedule IV, appears in other legal systems and international treaties, but the criteria and substances covered differ substantially. Where these pages refer to Schedule IV without qualification, they mean the US CSA tier.

What it means in practice

A Schedule IV substance requires a valid prescription. Federal regulations allow that prescription to be refilled up to five times within six months of its original issue date — more permissive than Schedule III, which allows three refills, but still more restricted than non-controlled medications.

Manufacturers, distributors, and dispensing pharmacies must register with the Drug Enforcement Administration and maintain required records. Possession without a valid prescription is a federal offense, as is distribution outside lawful channels.

Substances are placed in Schedule IV through either an act of Congress or a DEA administrative rulemaking process, which requires consultation with the Department of Health and Human Services. Obligations under international treaties — particularly the 1971 UN Convention on Psychotropic Substances — can also drive placement, as the US is bound to control substances listed in that treaty's schedules.

How jurisdictions vary

The 1971 UN Convention on Psychotropic Substances has its own Schedule IV — the treaty's least restrictive tier — covering a broad range of benzodiazepines and certain barbiturates. Both the CSA and the treaty number their schedules with I as the most restrictive, so the tier positions roughly correspond, but the criteria and substance lists are not identical.

Canada's Controlled Drugs and Substances Act uses the same four-schedule numbering but applies different criteria; its Schedule IV covers a distinct set of substances from the US tier, and the two should not be read as equivalent. Australia's Therapeutic Goods Administration uses Schedule 4 as a broad prescription-medicine category unrelated to abuse potential ranking — it is not a controlled-substances schedule in the same sense.

The United Kingdom uses a different framework entirely. Criminal penalties run through the Misuse of Drugs Act's Class A, B, and C system, while medicines licensing follows a separate track. The UK does not use Schedule I–V numbering.

What is contested

The CSA places most benzodiazepines in Schedule IV on the basis that they carry a low potential for abuse relative to Schedule III substances. Published literature on benzodiazepine dependence and discontinuation has been extensive; clinical guidelines in multiple countries treat long-term benzodiazepine use as a meaningful dependence risk requiring tapered withdrawal. The legal classification and the clinical and epidemiological record do not consistently align on this point. This page reports the classification as a legal fact; the evidence base for individual substances is addressed on their respective pages.

Scope and currency

This entry is not legal advice and does not describe the law in any reader's jurisdiction. Drug law changes through administrative action, court decisions, and legislation; the schedule position stated here may not reflect current law. It states the position as of August 2026.

The per-substance legal-status section on each substance page carries its own jurisdiction, date, and source — that is the value to rely on for any specific substance.