The DEA controlled substance schedules classify drugs by abuse potential and accepted medical use. Schedule I (no accepted medical use, high abuse potential: heroin, LSD, marijuana federally), Schedule II (high abuse potential with accepted medical use: oxycodone, morphine, fentanyl, amphetamines, methylphenidate), Schedule III (moderate abuse potential: buprenorphine, testosterone, codeine combinations), Schedule IV (low abuse potential: benzodiazepines, zolpidem, tramadol), Schedule V (lowest abuse potential: pregabalin, cough preparations with small amounts of codeine). NPs must hold a valid DEA registration and comply with state-specific prescriptive authority regulations for controlled substances.