Weekdays 6 AM - 8 PM Weekends 7 AM-5 PM PST

Your prescription - Your Choice

Choose either the B (Brand) or the G (Generic) alternative below:
  • Step 1.

(Isosorbide Mononitrate)

Formulation : Extended Release Tablet

symbol_rx Prescription Required

Isosorbide Mononitrate ER
(Generic alternative to Imdur)

Formulation : Tablet

symbol_rx Prescription Required

What is Imdur /Isosorbide Mononitrate used for?

Imdur is used to prevent angina attacks (chest pain).  Imdur is in a group of drugs called nitrates.  These drugs dialate blood vessels making it easier for blood to flow through them and easier for the heart to pump blood.  Imdur will not treat an attack that has already started.

How should Imdur /Isosorbide Mononitrate be stored?

Store Imdur at room temperature away from moisture, heat, and light.  Keep the bottle tightly closed away from children and pets.

General information

This medication should only be used by prescribed patient, do not give it to other people. The information provided is advisory only and does not contain all information pertaining to this medication. Talk to your doctor, pharmacist, or health care provider for question about this medication.

How should I take Imdur/Isosorbide Mononitrate ?

Take Imdur as prescribed to your by a doctor.  Do not take this medication in larger amounts, or for longer than prescribed.  Your doctor may change your dose to make sure you get the most benefit from Imdur.  Try to rest or stay seated when you use this medication. Imdur can cause dizziness or fainting.  Take this medication with atleast 4 ounces of water.  Do not crush, chew, or break a tablet.  Swallow the pill whole.  Breaking an Imdur tablet may cause too much medicine to be released at once.  this medication may cause you to have unusual results with certain medical tests.  Tell any doctor who treats you that you are using Imdur. Your blood pressure may become low while using Imdur if you are experiencing vomiting, diarrhea, heavy sweating, heart disease, dialysis, a low-salt diet, or taking diuretics.  Tell your doctor if you have an illness that causes diarrhea or vomiting.  Keep taking this medication to prevent an angina attack.  Have your prescription filled before it runs out.  Do not stop taking Imdur suddenly.  This could cause a severe angina attack.  If you miss a dose, take the missed dose as soon as you remember.  If it is almost time for your next dose, skip the missed dose and continue with your regular dosing regime.  Do not take extra medicine to make up for the missed dose.

When should Imdur /Isosorbide Mononitrate not be taken?

Do not use Imdur if you are taking sildenafil (Viagra).  Life-threatening side effects can occur if you take Imdur with a sildenafil.   Do not use Imdur if you are allergic to isosorbide mononitrate, isosorbide dinitrate, (Isordil, Dilatrate, Isochron), or nitroglycerin, or if you have early signs of a heart attack.

What precautions should I follow when taking Imdur /Isosorbide Mononitrate ?

Before taking Imdur, tell your doctor if you have congestive heart failure, low blood pressure, or kidney disease.  Tell your doctor if you are pregnant or plan to become pregnant before using Imdur.  If you become pregnant during treatment, inform your doctor at once. It is not known whether Imdur passes into breastmilk and if it could harm a nursing baby.  Do not use this medication without informing your doctor if you are breast-feeding a baby.

What special warning(s) should I be aware of when taking Imdur /Isosorbide Mononitrate ?

Imdur can cause severe headaches, especially when it is first used.  These headaches gradually become less severe as you continue using Imdur.  Do not stop taking it if you experience headaches.  Ask your  doctor before using any medication for headaches.  Do not stop taking Imdur suddenly as this could cause a serious angina attack. Imdur can cause side effects that can impair your thinking or reactions.  Be careful if you drive or do anything dangerous requiring you to be awake and alert.  Try not to get up too fast from sitting or lying down.  You may feel dizzy.   Avoid drinking alcohol because it can increase some of the side effects caused by Imdur. 

When should Imdur /Isosorbide Mononitrate not be taken?

Seek emergency medical help if you have any signs of an allergic reaction including: hives, difficulty breathing, swelling of the face, lips, tongue, or throat.  Inform your doctor immediately if you have serious side effects such as: a fast, slow, pounding, or uneven heart beat, feeling like you may pass out, trouble breathing, blue coloured skin, tired feeling, or worsening angina pain.

Less serious side effects include: headache, mild dizziness, warmth, redness, or tingling under your skin, nausea, vomiting, constipation, or diarrhea, pain or stiffness in your joints or muscles, hot flashes, or dry mouth.