Ranolazine (142387-99-3) is an FDA-approved drug used for the treatment of chronic angina. It inhibits the late inward sodium current in heart muscle leading to decreased intracellular calcium levels.¹ Ranolazine blocks Nav 1.4, 1.5, 1.7 and 1.8 (IC₅₀'s = 2.42, 6.22, 1.72(10.33), 21.53 μM respectively.

References/Citations
1) Belardinelli et al., (2006), Inhibition of the late sodium current as a potential cardioprotective principle: effects of the late sodium current inhibitor ranolazine; Heart, 92 iv6
2) Wang et al. (2008), State- and Use-Dependent Block of Muscle Nav1.4 and Neuronal Nav1.7 Voltage-Gated Na+-Channel Isoforms by Ranolazine; Mol. Pharmacol. 73 940
3) Rajamani et al., (2008), Block of tetrodotoxin-sensitive, Na(V)1.7 and tetrodotoxin-resistant, Na(V)1.8, Na+ channels by ranolazine; Channels(Austin) 2 449