Adalat (Nifedipine) is a calcium antagonist belonging to the dihydropyridine. Nifedipine selectively inhibits and at very low concentrations, the entry of calcium ions at the voltage-dependent L-type channels This action is exerted mainly on vascular smooth muscle and to a lesser extent in the heart muscle.
Nifedipine reduces arterial vascular tone by this mechanism and causes peripheral and coronary vasodilation. In normal coronary perfusion, decreased afterload caused by nifedipine contributes to a decrease in cardiac workload and myocardial oxygen consumption, normal or ischemic.
Nifedipine, dilates the coronary arteries of the endocardium and epicardium, provides an increase in oxygen supply to the heart.
The increase in coronary blood flow is particularly clear in the non-ischemic myocardium and was also demonstrated in the ischemic myocardium, provided that the coronary perfusion pressure does not drop excessively, in this case, coronary steal phenomenon may occur, resulting in a paradoxical exacerbation of angina attacks. These exacerbations are the result of excessive hypotension (decrease in coronary flow) and reflex tachycardia (increased cardiac workload and oxygen consumption).
By inhibiting the entry of calcium into cardiac myocyte Nifedipine, like other calcium channel blockers, is negative inotropic.
This effect is normally neutralized by reflex stimulation of the sympathetic and renin-angiotensin systems, following the deactivation of baroreflex.
If excessive hypotension, increased heart rate and ventricular arrhythmias may occur.
With their complementary pharmacological mechanisms of action, the combination of nifedipine with beta-blockers leads to a synergistic effect.
In animals, depending on the model, nifedipine inhibits the accumulation of cholesterol in the walls of the aorta and arteries of conduction diminishes the migration and proliferation of smooth muscle cells.
In prolonged treatment, there was no evidence of weight gain. This item is for a lack of fluid retention.
Nifedipine did not alter the lipid and carbohydrate metabolism.