Content

Vasodilators are medications that open (dilate) blood vessels. They affect the muscles in the walls of the arteries and veins, preventing the muscles from tightening and the walls from narrowing.

As a result, blood flows more easily through the vessels. The heart doesn't have to pump as hard, reducing blood pressure.

Some drugs used to treat hypertension, such as calcium channel blockers also dilate blood vessels. But the vasodilators that work directly on the vessel walls are hydralazine and minoxidil.