Dextrorphan-d3 (tartrate) (Item No. 15810) is intended for use as an internal standard for the quantification of dextrorphan (tartrate) by GC- or LC-MS. Dextrorphan is categorized as an arylcyclohexylamine and is a metabolite of dextromethorphan (hydrobromide hydrate) , an antitussive found in cough medicines. Dextrorphan, while also having antitussive activity, is psychoactive, leading to the abuse of cough medicines containing the parent compound. Dextrorphan antagonizes NMDA and μ-opioid receptors (Kis = 54 and 420 nM, respectively) and inhibits norepinephrine and serotonin transporters (Kis = 340 and 401 nM, respectively). This product is intended for research and forensic applications.