DefinitionDrug abuse is the use of illegal drugs, or the misuse of prescription or over-the-counter drugs for at least a year with negative consequences.See also:Drug abuse and dependenceDrug abuse first aidAlternative NamesSubstance abuse; Illicit drug abuse; Narcotic abuse; Hallucinogen abuseInformationMARIJUANA (also called "grass," "pot," "reefer," "joint," "hashish," "cannabis," "weed," and "Mary Jane")About 2 in 5 Americans have used marijuana at least once. About 10% of the population uses it on a regular basis.The source of marijuana is the hemp plant (cannabis sativa). The active ingredients are THC (delta-9-tetrahydrocannabinol) and other cannabinoids, which are found in the leaves and flowering shoots of the plant.Hashish is a substance taken from the tops of female plants. It c