seproxetine seproxetine seproxetine, also known as (s)-norfluoxetine, is a selective serotonin reuptake inhibitor (ssri). it is the s enantiomer of norfluoxetine, the main active metabolite of the widely used antidepressant fluoxetine; but little is known about its pharmacological actions. seproxetine was being investigated by eli lilly and company as an antidepressant; however, cardiac side effects were discovered and development was discontinued. seproxetineclinical dataatc codenonelegal statuslegal status in general: uncontrolled pharmacokinetic dataelimination half-life4–16 daysidentifiers iupac name (s)-3-phenyl-3-propan-1-amine cas number126924-38-7pubchem cid4541iuphar/bps208drugbankdb06731chemspider4382unii25co3x0r31comptox dashboard (epa)dtxsid80866540 chemical and physical dataformulac16h16f3nomolar mass295.305 g·mol−1