What are the most commonly used drugs?

The most commonly used drugs include alcohol, cannabis, nicotine, prescription medications used non‑medically, and illicit substances such as cocaine, methamphetamine, and opioids.

Alcohol, nicotine, and cannabis are used far more frequently than other substances because they are widely available and, in some cases, socially accepted or legally regulated. Prescription drugs—such as opioid pain medications, stimulants, and sedatives—are also commonly misused when taken without a prescription or in ways other than prescribed. Illicit drugs like cocaine, methamphetamine, and heroin are used by a smaller portion of the population but carry high risks for addiction and harm.

Patterns of use vary based on age, region, access, and social environment. Some drugs are more common in certain communities or settings, while others fluctuate over time due to changes in availability, cost, or enforcement. Polysubstance use—using more than one drug at the same time or over the same period—is also common and can increase risks.

In context, understanding which drugs are most commonly used helps explain why substance‑related problems affect people from many different backgrounds, not just those using illicit or highly stigmatized substances.