Medetomidine

Medetomidine is a veterinary anesthetic medication with potent sedative effects. As of December 2025, it is an emerging illicit drug adulterant. It is a racemic mixture of two stereoisomers, levomedetomidine and dexmedetomidine, the latter being the isomer with the pharmacologic effect as an alpha 2- adrenergic agonist. Effects can be reversed using atipamezole. It was developed by Orion Pharma. It is approved for dogs in the United States, and distributed in the United States by Pfizer Animal Health and by Novartis Animal Health in Canada under the product name Domitor. Starting in 2022 medetomidine has been detected in the US in samples of illicit drugs and associated with overdoses. The free base form of medetomidine is sold as an antifouling substance for marine paints.