scheduled drug
any of various drugs whose prescription or use has been restricted by the U.S. Drug Enforcement Administration in accordance with the Controlled Substances Act of 1970. Schedule I drugs are those for which all nonresearch use is illegal (e.g., LSD, heroin). Schedule II drugs include most opiates, stimulants (e.g., cocaine, amphetamines, methylphenidate), barbiturates, and prescribed forms of tetrahydrocannabinol (dronabinol). For Schedule II drugs, no refills or telephone prescriptions are permitted. Schedule III drugs include some opioids, barbiturates, and stimulants subject to abuse; prescriptions must be rewritten after 6 months, with a maximum of five refills. Schedule IV drugs include certain opioids, some stimulants, and most of the benzodiazepines. Refills are limited to five, and prescriptions must be rewritten after 6 months. Schedule V drugs include several opiates with low abuse potential (low doses of codeine and others). The Schedule of Controlled Substances,
originally designed to restrict the prescription of commonly abused drugs, is periodically updated as the popularity of new agents—generally drugs of abuse—reaches the attention of authorities.