Classes or schedules are determined by the Drug Enforcement Agency (DEA), an arm of the United States Justice Department, and are based on the potential for abuse and dependence liability (physical and psychological) of the medication. Some states may have stricter prescription regulations. Physicians, dentists, podiatrists, and veterinarians may prescribe controlled substances. Nurse practitioners and physician's assistants may prescribe controlled substances with limitations that vary from state to state.
Schedule I (C-I)
Potential for abuse is so high as to be unacceptable. May be used for research with appropriate limitations. Examples are LSD and heroin.
Schedule II (C-II)
High potential for abuse and extreme liability for physical and psychological dependence (amphetamines, opioid analgesics, dronabinol, certain barbiturates). Outpatient prescriptions must be in writing. In emergencies, telephone orders may be acceptable if a written prescription is provided within 72 hr. No refills are allowed.
Schedule III (C-III)
Intermediate potential for abuse (less than C-II) and intermediate liability for physical and psychological dependence (certain nonbarbiturate sedatives, certain nonamphetamine CNS stimulants, and certain opioid analgesics). Outpatient prescriptions can be refilled 5 times within 6 mo from date of issue if authorized by prescriber. Telephone orders are acceptable.
Schedule IV (C-IV)
Less abuse potential than Schedule III with minimal liability for physical or psychological dependence (certain sedative/hypnotics, certain antianxiety agents, some barbiturates, benzodiazepines, chloral hydrate, pentazocine, and propoxyphene). Outpatient prescriptions can be refilled 6 times within 6 mo from date of issue if authorized by prescriber. Telephone orders are acceptable.
Schedule V (C-V)
Minimal abuse potential. Number of outpatient refills determined by prescriber. Some products (cough suppressants with small amounts of codeine, antidiarrheals containing paregoric) may be available without prescription to patients >18 yr of age.
Controlled Substances Schedules is a sample topic found in Davis's Drug Guide.
To find other Davis's Drug Guide topics please log in or purchase a subscription.