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Imdur

Generic name: isosorbide mononitrate

What is Imdur used for?

  • Imdur is used to prevent chest pain.
  • Imdur may be given to you for other reasons. Talk to your doctor.

Before taking Imdur, tell your doctor:

  • If you are allergic to Imdur; any part of this medicine; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
  • If you have heart failure (weak heart).
  • If you have had a recent heart attack.
  • If you are taking any of these drugs: Avanafil, riociguat, sildenafil, tadalafil, or vardenafil.

This is not a list of all drugs or health problems that interact with this medicine.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take Imdur with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take Imdur?

  • Tell all of your health care providers that you take Imdur. This includes your doctors, nurses, pharmacists, and dentists.
  • Avoid driving and doing other tasks or actions that call for you to be alert until you see how Imdur affects you.
  • To lower the chance of feeling dizzy or passing out, rise slowly if you have been sitting or lying down. Be careful going up and down stairs.
  • Check your blood pressure as you have been told.
  • This medicine may affect certain lab tests. Tell all of your health care providers and lab workers that you take Imdur.
  • Talk with your doctor before you drink alcohol.
  • If you are taking Imdur for chest pain, it will not treat chest pain as it happens. This medicine is only used to prevent or lower the number of chest pain attacks.
  • If you have chest pain or pressure that is new or worse, get emergency medical care right away.
  • If you have been taking Imdur for a long time without a break, it may not work as well. This is known as tolerance. Be sure to have a "nitrate-free" period of time each day. Talk with your doctor if Imdur stops working well. Do not take more than ordered.
  • If you are 65 or older, use Imdur with care. You could have more side effects.
  • You may see something that looks like the tablet in your stool. This is normal and not a cause for concern. If you have questions, talk with your doctor.
  • Tell your doctor if you are pregnant, plan on getting pregnant, or are breast-feeding. You will need to talk about the benefits and risks to you and the baby.

How is Imdur best taken?

Use Imdur as ordered by your doctor. Read all information given to you. Follow all instructions closely.

  • Do not stop taking Imdur all of a sudden without calling your doctor. You may have a greater risk of side effects. If you need to stop Imdur, you will want to slowly stop it as ordered by your doctor.
  • If you are taking Imdur once a day, take it in the morning when you get up unless your doctor tells you otherwise.
  • Swallow whole. Do not chew, break, or crush.
  • Some products may be broken in half. Talk with the doctor.

What do I do if I miss a dose?

  • Take a missed dose as soon as you think about it.
  • If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
  • Do not take 2 doses at the same time or extra doses.

What are the side effects of Imdur that I need to call my doctor about immediately?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Very bad dizziness or passing out.
  • Fast or slow heartbeat.
  • Chest pain that is new or worse.

What are some other side effects of Imdur?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

  • Dizziness.
  • You may have headaches when you start taking Imdur. Most of the time it gets better with time. Do not change how you use Imdur to avoid these headaches. Talk with your doctor for ways to lessen this side effect.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

If overdose is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Imdur Images

How do I store and/or throw out Imdur?

  • Store at room temperature.
  • Store in a dry place. Do not store in a bathroom.
  • Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
  • Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.

Consumer information use and disclaimer

  • If your symptoms or health problems do not get better or if they become worse, call your doctor.
  • Do not share your drugs with others and do not take anyone else's drugs.
  • Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about Imdur, please talk with your doctor, nurse, pharmacist, or other health care provider.
  • If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

This information should not be used to decide whether or not to take Imdur or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to Imdur. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.

Source: Wolters Kluwer Health. Last updated April 5, 2023.