Nitro-Dur® (
nitroglycerin patch) is a prescription skin patch specifically approved for preventing
angina pectoris associated with
coronary artery disease. This means that this drug is approved to help prevent episodes of chest pain caused by coronary artery disease (also known as coronary
heart disease), a condition in which the small blood vessels that supply oxygen to the heart become too narrow to adequately supply the heart with enough blood and oxygen.
Nitro-Dur does not work quickly enough to stop an
angina attack that is already occurring. Therefore, this medicine is not appropriate for people who have only occasional or rare episodes of angina. It is also inappropriate for people who have angina due to other causes.
Nitro-Dur works by relaxing the veins and arteries in the body. With the arteries and veins relaxed, the heart does not need to work so hard and does not require as much oxygen. Because angina is usually caused when there is not enough oxygen to meet the heart's needs, using Nitro-Dur can help prevent angina attacks.
Because the body rapidly becomes accustomed to the effects of
nitroglycerin when it is used around the clock, it is essential that a 10- to 12-hour break from Nitro-Dur occurs every day
(see Nitro-Dur Dosage). Without this break, the drug will become ineffective within 24 hours.