Misuse of Drugs Act

British legislation

Also known as: MDA

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Last updated

July 19, 2026

Quick Summary

The Misuse of Drugs Act (MDA) is the primary legislation in the United Kingdom for controlling the manufacture, distribution, and sale of narcotics. Introduced in 1971, it replaced earlier laws and established a classification system for drugs based on their potential for abuse.12

The MDA categorizes drugs into three classes:
* Class A: Includes substances like heroin and LSD.12
* Class B: Cannabis falls into this category.12
* Class C: Encompasses substances such as tranquilizers and anabolic steroids.1

This system is similar to the Controlled Substances Act (CSA) in the United States, which also classifies drugs based on abuse potential and medical use, though the CSA has five schedules. The MDA, however, does not classify alcohol or tobacco as controlled substances.31

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drug use
National controls
In 1971 the Misuse of Drugs Act (MDA), which has been amended multiple times but remains the country’s primary means of drug control, replaced the Dangerous Drug Act of 1965, which itself had replaced earlier legislation stemming from the 1912 Hague Convention. Similar to the CSA in the…
Read More
In 1971 the Misuse of Drugs Act (MDA), which has been amended multiple times but remains the country’s primary means of drug control, replaced the Dangerous Drug Act of 1965, which itself had replaced earlier legislation stemming from the 1912 Hague Convention. Similar to the CSA in the…
Read More