Amlodipine (brand name Amonex) is a medication used to lower blood pressure and prevent chest pain. It belongs to a group of medications known as long-acting dihydropyridine-type (DHP) calcium channel blockers. Like other medications in this group, amlodipine lowers blood pressure by relaxing the muscles controlling the diameter of blood vessels in the body. Widening of these blood vessels lowers blood pressure. In angina, amlodipine increases blood flow to the heart muscle to relieve pain due to angina. It is indicated for the treatment of essential hypertension, chronic stable angina pectoris and Prinzmetal angina.