Cilnidipine is a dihydropyridine calcium-channel blocker. Cilnidipine binds to the dihydropy-ridine binding sites of the L-type voltage dependent calcium channel and inhibits Ca2+ influx across the cell membranes of vascular smooth muscle cells via this channel, consequently vascular smooth muscle is relaxed, causing vasodilation. Cilnidipine inhibits Ca2+ influx via N-type voltage dependent calcium channels in the sympathetic nerve cell membrane. The inhibition of Ca2+ influx via N-type voltage dependent calcium channel was observed over a similar range of drug concentrations to those inhibiting L-type voltage dependent Ca2+ channels. Consequently, release of norepinephrine from sympathetic nerve terminals would be inhibited. Cilnidipine is considered to suppress the reflex increase in heart rate after blood pressure reduction.