Generic Monoket

Common use

Monoket is used for treating and preventing angina. It can be used to decrease the frequency and severity of anginal (chest pain) episodes and to reduce the need for sublingual (under the tongue) nitroglycerin. Monoket is in a group of drugs called nitrates. It makes it easier for blood to flow through them and easier for the heart to pump. Monoket will not treat an angina attack that has already begun.



Dosage and direction

Dosage of Monoket depends on prescription of your doctor. Do not take it in larger amounts or for longer than it was recommended. Follow the directions on your prescription schedule. Your doctor may suddenly change your dose to make sure you get the best results from this medication. Not all brands and forms of Monoket are taken in the same way. Follow your doctor's dosing instructions very carefully. Take this medication with water or other liquid. Do not crush, chew, or break an extended-release tablet. The best way to take it is to swallow the pill whole. Breaking the pill may cause too much of the drug to be released at one time. It is important to keep taking this medicine as directed to prevent an angina attack.



Precautions

Try to rest or stay seated when you use this medication. Monoket can cause dizziness or fainting. Get up slowly and steady yourself to prevent a fall. Before taking isosorbide mononitrate, tell your doctor if you have congestive heart failure, low blood pressure, or kidney disease. It is important to keep taking this medicine as directed to prevent an angina attack. Get your prescription refilled before you run out of medicine completely. You should not stop taking isosorbide mononitrate suddenly. Stopping suddenly could cause a severe angina attack. Never change brands of isosorbide mononitrate without the approval of your doctor. If you experience something like congestive heart failure, low blood pressure or kidney disease, you may need a dose adjustment or special tests to safely take Monoke. Tell your doctor if you have a prolonged illness that causes diarrhea or vomiting.

Be careful if you drive or do anything that requires you to be awake and alert. Avoid drinking alcohol. It can increase some of the side effects of Monoket.



Contraindications

You should not take Monoket if you have hypersensitivity to this drug (its components), hypotension, volume depletion, acute MI, CHF and hypertrophic cardiomyopathy.



Possible side effects

The most common side effect of Monoket is headache and it usually is related to increase of dose. Monoket may cause a severe drop in blood pressure when rising from a sitting position, causing dizziness, palpitations, and weakness. To reduce the risk of low blood pressure, patients should rise slowly from a sitting position. You need emergency medical help if you have any of signs of an allergic reaction (hives, difficulty breathing, swelling of your face, lips, tongue, or throat). Serious side effects include fast, slow, pounding, or uneven heart rate; feeling like you might pass out; trouble breathing, blue-colored skin, tired feeling or worsening angina pain. Less serious side effects may include headache, mild dizziness; warmth, redness, or tingling under your skin; nausea, vomiting, constipation, diarrhea; pain or stiffness in joints or muscles; hot flashes; or dry mouth.



Drug interactions

Patients taking Monoket should not receive sildenafil, tadalafil or vardenafil. Because sildenafil (Viagra), tadalafil (Cialis) and vardenafil (Levitra) increase the blood pressure lowering effects of Monoket and may cause excessive reductions in blood pressure.

Also severe reductions in blood pressure, especially when changing posture (orthostatic hypotension), may occur when Monoket is combined with diltiazem (Cardizem, Dilacor, Tiazac and several others), verapamil (Calan, Verelan, Verelan PM, Isoptin, Isoptin SR, Covera-HS), which also reduce blood pressure. Also inform your doctor about all other medications you use: blood pressure medication; dihydroergotamine (D.H.E. 45, Migranal) or ergotamine (Ergomar, Cafergot); an erectile dysfunction medication; a beta-blocker such as atenolol (Tenormin, Tenoretic), carvedilol (Coreg), labetalol (Normodyne, Trandate), metoprolol (Lopressor, Toprol), nadolol (Corgard), propranolol (Inderal, InnoPran), sotalol (Betapace), and others; or a calcium channel blocker such as diltiazem (Cartia, Cardizem), felodipine (Plendil), nifedipine (Nifedical, Procardia), verapamil (Calan, Covera, Isoptin, Verelan), and others.



Missed dose

Take the missed dose as soon as you remember. If it is almost time for your next dose, wait until then to take the medicine and skip the missed dose. Do not take extra medicine to make up the missed dose



Overdose

Overdose symptoms may include a severe throbbing headache, fever, confusion, dizziness or spinning sensation, fast or pounding heartbeats, vision problems, nausea, vomiting, stomach pain, bloody diarrhea, trouble breathing, sweating, cold or clammy skin, feeling light-headed, fainting, and seizure (convulsions). An overdose of Monoket can be fatal. Seek emergency medical attention if you think you have used too much of this medicine.

Storage

Store Monoket at room temperature15-30 C (59-86 F) in a tight container, away from moisture, heat, and light. Keep the bottle tightly closed when not in use.



Disclaimer

We provide only general information about medications which does not cover all directions, possible drug integrations, or precautions. Information at the site cannot be used for self-treatment and self-diagnosis. Any specific instructions for a particular patient should be agreed with your health care adviser or doctor in charge of the case. We disclaim reliability of this information and mistakes it could contain. We are not responsible for any direct, indirect, special or other indirect damage as a result of any use of the information on this site and also for consequences of self-treatment.

Clinical Verification

Last Clinically Updated: August 15, 2026

Written By

Dr. Elena Vance, PharmD

Clinical Specialist in Neuropharmacology

Fact Checked By

Marcus Thorne, MS

Biomedical Data & FDA Label Verification

Medically Reviewed By

Dr. Arthur Campbell, MD

Board-Certified Psychiatrist (ABPN)