Purity >95%. Mibefradil is a general calcium channel blocker that shows modest selectivity for T-type channels over L-type channels (IC50 = 2.7 and 18.6 μM, respectively). It is a potent vasodilator, increasing coronary artery flow with an EC50 value of 54 nM. Mibefradil has minimal negative inotropic effects, supporting its use as an anti-hypertensive agent.