8-[1-(4-Chlorophenyl)ethyl]-1-phenyl-1,3,8-triazaspiro[4.5]decan-4-one, commonly known as spirochlorphine, is a spirotriazole and a synthetic opioid belonging to the orphine opioids, a group of related new synthetic opioids.

Spirochlorphine is structurally related to brorphine and bezitramide, both of which are controlled under Schedule I of the United Nations 1961 Single Convention on Narcotic Drugs because of the public health and social risks they pose.
Spirochlorphine is monitored by the EUDA as a new psychoactive substance through the European Union Early Warning System (EWS), in accordance with Regulation (EU) 2023/1322 (1).

Since 2024, a marked increase has been observed in the number of orphine opioids identified on the European drug market, with nine new substances reported, including spirochlorphine.

Spirochlorphine was formally notified as a new psychoactive substance by the EUDA on behalf of Sweden on 15 April 2025 (2,3). The notification was based on the identification of the substance in 0.80 grams of white powder that was seized by police on 3 January 2025. The substance was analytically confirmed using GC-MS and NMR.