Milnacipran hydrochloride is a serotonin-norepinephrine reuptake inhibitor (SNRI) used in depression research. It is the enantiomer of the fibromyalgia treatment milnacipran. This compound is applied in neuropharmacology studies, including in vitro transporter assays and in vivo behavioral models, and has been associated with rare, transient serum aminotransferase elevations.