GTN spay and tablets; Isosorbide mononitrate; Isosorbide dinitrate

These are most commonly used in the treatment of angina. They work by relaxing muscle in the walls of arteries so opening them up. They affect arteries all over the body including those that supply the heart. As a result the supply of blood to the heart muscle is increased improving the symptoms of angina. GTN works very rapidly and is used to give quick relief from attacks of angina. It works best if used before undertaking exertion likely to cause an anginal attack. The most common side effect of these drugs is headache.