Controlled Substance
A drug whose manufacture, possession, and use are regulated due to potential for abuse or dependence. Controlled substances are classified into schedules based on medical utility and abuse potential. Most approved peptide drugs are not controlled substances because peptides generally have low abuse potential.
Technical Context
US scheduling (Controlled Substances Act, 21 USC 811-812): Schedule I (high abuse potential, no accepted medical use — e.g. heroin, LSD, MDMA), Schedule II (high abuse potential with accepted medical use — e.g. morphine, fentanyl, amphetamine), Schedule III (moderate abuse potential — e.g. anabolic steroids, ketamine), Schedule IV (lower abuse potential — e.g. benzodiazepines), Schedule V (lowest abuse potential — e.g. low-dose codeine cough preparations). Most approved peptide drugs are NOT scheduled because peptides generally have low abuse potential — they cannot typically be diverted for recreational use (injection requirement, specific receptor targeting, lack of euphoric effects). However, growth hormone (somatropin) is classified as Schedule III in some jurisdictions due to concerns about performance-enhancing use. The scheduling status directly affects prescribing requirements, record-keeping, storage, and penalties for unauthorised distribution.