Nitroglycerin patches are a vasodilator prescribed to relax the blood vessels in the body, thus relieving the chest pain of angina pectoris. The heart muscle is able to pump blood more efficiently when the blood vessels are not constricted. Preventing chest pain for people with heart disease is the most common use for nitroglycerin patches.
The nitroglycerin patch is designed to be worn for 12 to 14 hours a day, with at least 10 to 12 hours in between patch applications. Patch free times ensure the body does not develop a dependence on the medication, and also keeps the dosage at the minimum necessary for optimum cardiac function. Withdrawal symptoms may occur if the transdermal patch is suddenly discontinued.
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Before applying the nitroglycerin patch, hands must be carefully washed. The patch should be applied to the upper arms or on the chest. Changing the application site daily will prevent irritation to the skin from the adhesive on the patch. If the area is hairy, it must be shaved before the patch can be applied. The patch should be put on at the same time every day to ensure an even distribution of the medication in the bloodstream.
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Side effects of the nitroglycerin patch are persistent headaches, dizziness, and fainting. Care should be taken with daily activities, such as driving, until it is known how the person functions while on the patch. The patch may cause low blood pressure, and this can be exacerbated by drinking alcohol. Other side effects are irritation of the skin at the site of the patch adhesion, nausea, and vomiting. Some people report flushing of the face and upper chest.
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Adverse reactions to the nitroglycerin patch that should be reported to medical personnel are varied. Blurry vision, dry mouth, heavy sweating, and chest pain are not normal side effects of the patch. Unusual muscle weakness, a slow or fast heartbeat, or difficulty breathing should be evaluated promptly.
Severe allergic reactions to the nitroglycerin patch are indicated by a series of symptoms. Any severe swelling of the mouth, lips, throat, and face could indicate an allergic reaction. An allergic reaction can occur at any time while using the patch, even if it has been used without any problems in the past.
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Some people are not able to use the patch. Children and elderly people are not good candidates for the nitroglycerin patch. It is not known if the medication passes through breast milk, so the patch has not been deemed safe for use by breast feeding mothers. Pregnant women should not use the patch unless the benefits of the patch outweigh the risk for the fetus.