DEA places diphenidine in Schedule I of the Controlled Substances Act
The Drug Enforcement Administration placed diphenidine (1-(1,2-diphenylethyl)piperidine), including its salts, isomers, and salts of isomers, in Schedule I of the Controlled Substances Act by final rule published September 21, 2026 (91 FR 59695, FR Doc. 2026-19231), effective October 21, 2026. Anyone who manufactures, distributes, imports, exports, researches or possesses the substance becomes subject to Schedule I registration, security and recordkeeping requirements and to administrative, civil and criminal sanctions. The rule implements US obligations under the 1971 Convention on Psychotropic Substances.