Isosorbide Mononitrate, Oral

What are other names for this medicine?

Type of medicine: nitrate

Generic and brand names: isosorbide mononitrate, oral; ISMO; Imdur; Isotrate ER; Monoket

What is this medicine used for?

This medicine is used to reduce the frequency of attacks of angina (chest pain). Because it works slowly, it may not stop an attack that has already started. It may be used to treat other conditions as determined by your healthcare provider.

What should my healthcare provider know before I take this medicine?

Before taking this medicine, tell your healthcare provider if you have ever had:

• an allergic reaction to any medicine
• a head or brain injury
• a heart infection or fluid around the heart
• anemia
• glaucoma
• low blood pressure or high blood pressure that you take medicine to treat.

Females of childbearing age: Tell your healthcare provider if you are pregnant or plan to become pregnant. It is not known whether this medicine will harm an unborn baby. Do not breast-feed while taking this medicine without your healthcare provider's approval.

How do I take it?

Take this medicine exactly as your healthcare provider prescribes. You must take this medicine every day in order to prevent chest pains.

Take this medicine with a full glass (8 ounces) of water on an empty stomach (1 hour before or 2 hours after meals) for best results.

If your healthcare provider has prescribed ISMO, take it exactly as prescribed. Be sure to take the second dose of the day 7 hours after the first dose. If you miss a dose of ISMO, return to your regular schedule the next day, or ask your healthcare provider what to do.

If you are taking an extended-release form of this medicine, swallow the pills whole. Do not crush or break them. Your healthcare provider or pharmacist can tell you if you have an extended-release form of this medicine.

If you miss a dose, take it as soon as you remember unless it is almost time for the next scheduled dose. In that case, skip the missed dose and take the next one as directed. Do not take double doses. If you are not sure of what to do if you miss a dose, or if you miss more than one dose, contact your healthcare provider.

What should I watch out for?

Do not take sildenafil (Viagra), tadalafil (Cialis), or vardenafil (Levitra) while you are taking this medicine. Using these medicines together may cause severe or life-threatening low blood pressure. Taken with high blood pressure medicines, this medicine may cause extreme low blood pressure. Tell your provider about all the medicines you take.

Do not stop taking this medicine without your healthcare provider's approval. You may have to reduce your dosage gradually to avoid more chest pain.

You may have a headache for a short time after you take a dose of this medicine. It is a sign that the medicine is working. If you try to eliminate the headaches by reducing your dosage, you will reduce the effectiveness of the medicine. Ask your healthcare provider whether you should take aspirin or acetaminophen (Tylenol) to relieve these headaches.

You may feel dizzy or faint when you get up quickly after sitting or lying down. Getting up slowly may help. Also, drinking alcohol may make it worse. Do not drink alcohol unless your healthcare provider approves.

Over time, your body may stop responding to the medicine. This is called developing tolerance. Tell your healthcare provider if you think this medicine is not working as well for you as when you first started taking it.

What are the possible side effects?

Along with its needed effects, your medicine may cause some unwanted side effects. Some side effects may be very serious. Some side effects may go away as your body adjusts to the medicine. Tell your healthcare provider if you have any side effects that continue or get worse.

Life-threatening (Report these to your healthcare provider right away. If you cannot reach your healthcare provider right away, get emergency medical care or call 911 for help): Allergic reaction (hives; itching; rash; trouble breathing; tightness in your chest; swelling of your lips, tongue, and throat), very fast heartbeat, fainting.

Serious (report these to your healthcare provider right away): Severe headache, dry mouth, high or low blood pressure, blurred vision.

Other: Dizziness, short headache, flushing, nausea, vomiting.

What products might interact with this medicine?

When you take this medicine with other medicines, it can change the way this or any of the other medicines work. Nonprescription medicines, vitamins, natural remedies, and certain foods may also interact. Using these products together might cause harmful side effects. Talk to your healthcare provider if you are taking:

• beta blockers such as acebutolol (Sectral), atenolol (Tenormin), esmolol (Brevibloc), carteolol, bisoprolol (Zebeta), pindolol, metoprolol (Lopressor, Toprol XL), nadolol (Corgard), sotalol (Betapace), timolol, and propranolol (Inderal)
• calcium channel blockers such as diltiazem (Cardizem), felodipine (Plendil), isradipine (DynaCirc), nicardipine (Cardene), and verapamil (Calan, Isoptin, Verelan)
• ergot medicines such as dihydroergotamine (D.H.E. 45), ergotamine (Ergomar), ergonovine (Ergotrate), and methylergonovine (Methergine)
• heparin
• medicines to improve your circulation such as isoxsuprine (Vasodilan) and hydralazine (Apresoline)
• phenothiazines such as chlorpropamide (Thorazine), fluphenazine (Permitil, Prolixin), perphenazine, prochlorperazine (Compazine), promazine (Sparine), triflupromazine (Vesprin), thioridazine, and trifluoperazine (Stelazine)
• medicines to treat erectile dysfunction such as tadalafil (Cialis), sildenafil (Viagra) or vardenafil (Levitra). Using these medicines together is life threatening.

Do not drink alcohol while you are taking this medicine.

Keep a list of all your medicines (prescription, nonprescription, supplements, natural remedies, and vitamins) with you. Be sure that you tell all healthcare providers who treat you about all the products you are taking.

How should I store this medicine?

Store this medicine at room temperature. Keep the container tightly closed. Protect it from heat, high humidity, and bright light.

This advisory includes selected information only and may not include all side effects of this medicine or interactions with other medicines. Ask your healthcare provider or pharmacist for more information or if you have any questions.

Ask your pharmacist for the best way to dispose of outdated medicine or medicine you have not used. Do not throw medicine in the trash.

Keep all medicines out of the reach of children.

Do not share medicines with other people.