Arteriolar-vasodilators are used to treat different conditions, including high blood pressure, heart failure, and hair loss. These medications work by relaxing the small arteries (arterioles), which helps to lower blood pressure and improve blood flow. Some arteriolar-vasodilators come in oral forms, while others are available as injections. Examples include hydralazine (Apresoline), minoxidil (Men's Rogaine), and sodium nitroprusside (Nitropress).