Recreational drugs are substances that are used for non-medical purposes in order to experience the psychoactive effects of the substance. Drugs are often used recreationally based on the belief that occasional use will not be habit-forming or lead to addiction. Substances that are commonly used recreationally include depressants, stimulants, and psychotropics. According to the National Institute on Drug Abuse (NIDA), some of the most commonly used recreational drugs are marijuana, synthetic cannabinoids, prescriptions medications, and over-the-counter medications.