Relative to other SNRIs, levomilnacipran, as well as milnacipran, differ in that they are much more balanced reuptake inhibitors of serotonin and norepinephrine. To demonstrate, the serotonin:norepinephrine ratios of SNRIs are as follows: venlafaxine = 30:1, duloxetine = 10:1, desvenlafaxine = 14:1, milnacipran = 1.6:1, and levomilnacipran = 1:2. The clinical implications of more balanced elevations of serotonin and norepinephrine are unclear, but may include improved effectiveness, though also increased side effects.
Levomilnacipran is selective for the serotonin and norepinephrine transporters, lacking significant affinity for over 23 off-target sites. However, it does show some affinity for the dizocilpine (MK-801/) site of the NMDA receptor (K = 1.7 μM), and has been found to inhibit NR2A and NR2B subunit-containing NMDA receptors with respective IC values of 5.62 and 4.57 μM. As such, levomilnacipran is an NMDA receptor antagonist at high concentrations.
Levomilnacipran has recently been found to act as an inhibitor of beta-site amyloid precursor protein cleaving enzyme-1 (BACE-1), which is responsible for β-amyloid plaque formation, and hence may  be a potentially useful drug in the treatment of Alzheimer's disease.