Ifenprodil (NP-120), a cerebral vasodilator, is a noncompetitive NMDA receptor antagonist. Ifenprodil exerts high affinity at NR1A/NR2B receptors (IC50=0.34 µM) over 400-fold than at NR1A/NR2A receptors (IC50=146 µM)[1]. Ifenprodil is an alpha1 adrenergic receptor antagonist. Ifenprodil inhibits GIRK (Kir3), reduces inward currents through the basal GIRK activity. Ifenprodil has reliable inhibitory effects against A/H1N1 strains (EC50 of 6.6 µM). Ifenprodil has neuroprotective, anticonvulsant and antinociceptive effects. Ifenprodil can be used for the study of cerebrovascular diseases and peripheral arterial obliterative disease[2][4].