This medication is used before physical activities (such as exercise, sexual activity) to prevent chest pain (angina) in people with a certain heart condition (coronary artery disease). It may also be used to relieve chest pain in these people once it occurs.
Nitroglycerin belongs to a class of drugs known as nitrates. Angina occurs when the heart muscle is not getting enough blood. This drug works by relaxing and widening blood vessels so blood can flow more easily to the heart.
Ask your doctor now for exact instructions on how to use your nitroglycerin and when to call for emergency medical help (911).
Read the Patient Information Leaflet if available from your pharmacist before you start using nitroglycerin and each time you get a refill. If you have any questions, ask your doctor or pharmacist.
Sit down before using this medication. Place 1 tablet under the tongue and allow it to dissolve as directed by your doctor. Do not chew or swallow the tablet. The dosage is based on your medical condition and response to treatment.
If you are using this medication to prevent chest pain before physical activities, use it 5 to 10 minutes before the activity.
If you are using this medication to relieve chest pain once it occurs, use it as soon as possible. If your chest pain has not improved or if it has worsened 5 minutes after you use this drug, call emergency medical help (911). After calling the emergency number, use another dose. Five minutes after the second dose, if you still have chest pain and the ambulance has not arrived, use a third dose. If your chest pain is not gone after 15 minutes and 3 doses of nitroglycerin, call emergency medical help (911) if you have not called already. Do not use more than 3 doses during an attack unless directed by your doctor.
Headache, dizziness, lightheadedness, nausea, flushing, and burning/tingling under the tongue may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.
Headache is often a sign that this medication is working. Your doctor may recommend treating headaches with an over-the-counter pain reliever (such as acetaminophen, aspirin). If the headaches continue or become severe, tell your doctor promptly.
To reduce the risk of dizziness and lightheadedness, get up slowly when rising from a sitting or lying position.
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor immediately if these unlikely but serious side effects occur: fainting, fast/irregular/pounding heartbeat.
A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any of the following symptoms of a serious allergic reaction: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
Before using this medication, tell your doctor or pharmacist if you are allergic to it; or to similar drugs (such as isosorbide mononitrate); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
This medication should not be used if you have a certain medical condition. Before using this medicine, consult your doctor or pharmacist if you have: recent head injury.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: anemia, low blood pressure, loss of too much body water (dehydration), other heart problems (such as recent heart attack).
This drug may make you dizzy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages.
Before having surgery, tell your doctor or dentist that you are using this medication.
Older adults may be more sensitive to the side effects of this medication, especially dizziness and lightheadedness which could increase the risk of falls.
During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.
It is unknown if this medication passes into breast milk or if it may harm a nursing infant. Consult your doctor before breast-feeding.
Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with them first.
This drug should not be used with the following medications because very serious (possibly fatal) interactions may occur: drugs to treat erectile dysfunction-ED or pulmonary hypertension (such as sildenafil, tadalafil), riociguat.
If you are currently using any of these medications, tell your doctor or pharmacist before starting nitroglycerin.
Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: rosiglitazone, certain drugs to treat migraine headaches (ergot alkaloids such as ergotamine).
This medication may interfere with certain laboratory tests (including blood cholesterol levels), possibly causing false test results. Make sure laboratory personnel and all your doctors know you use this drug.
This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.
If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: slow heartbeat, vision changes, severe nausea/vomiting, sweating, cold/clammy skin, bluish fingers/toes/lips.
Do not share this medication with others.
Store at room temperature at 68-77 degrees F (20-25 degrees C) away from light, heat, and moisture. Do not store in the bathroom. Keep in the original glass bottle with the cap tightly closed. Ask your pharmacist how long this medication will continue to work properly after the bottle is opened for the first time. Keep all medicines away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.
MEDICAL ALERT: Your condition can cause complications in a medical emergency. For information about enrolling in MedicAlert, call 1-888-633-4298 (US) or 1-800-668-1507 (Canada).
Information last revised March 2014. Copyright(c) 2014 First Databank, Inc.
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