Scheduled substance
DEA-classified controlled drug. Schedule I (illegal) to V (least restricted).
Schedule II (Adderall, oxycodone, fentanyl) is highest medical restriction. Schedule III (testosterone, ketamine). Schedule IV (Xanax, Klonopin, Ambien). Schedule V (low-dose codeine). Telehealth rules vary by schedule under the 2025 DEA rule.