Duloxetine-d3 is intended for use as an internal standard for the quantification of duloxetine by GC- or LC-MS. (S)-Duloxetine is a potent inhibitor of serotonin and norepinephrine reuptake (Kis = 4.6 and 15.6 nM, respectively, for rat synaptosomes). It also inhibits dopamine reuptake (Ki = 369 nM). (S)-Duloxetine suppresses spontaneous firing activity in vivo in the dorsal raphe and locus coeruleus (ED50s = 99 and 475 μg/kg, respectively). It also decreases immobility time and increases latency to first immobility in the forced swim test in mice when administered at doses of 16 and 32 mg/kg. Formulations containing (S)-duloxetine have been used in the treatment of major depressive disorder, generalized anxiety disorder, chronic neuropathic and musculoskeletal pain, and fibromyalgia.
