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Nitrate (vasodilator)

Isosorbide mononitrate: uses, side effects & precautions

Also known as Imdur, Monoket, Ismo, Elantan.

Deze informatie is uitsluitend bedoeld als algemene richtlijn en vormt geen medisch advies. Raadpleeg altijd een gekwalificeerde zorgprofessional voor persoonlijke medische vragen. Bel in geval van nood uw lokale alarmnummer.

What it is used for

  • Preventing chest pain from angina (long-term control)

How it works

Isosorbide mononitrate relaxes and widens blood vessels, which reduces the workload on the heart and improves blood flow to the heart muscle. This helps prevent episodes of angina.

How it is taken

Taken by mouth as a tablet, including immediate-release and once-daily extended-release forms. It is used regularly to prevent angina rather than to relieve a sudden attack. Take it exactly as your doctor or pharmacist directs and follow the label, including any advised gap each day, which helps the medicine keep working; swallow extended-release tablets whole.

No doses here on purpose. The right strength and schedule depend on you — only a doctor or pharmacist should set them. Always follow your prescription and the label.

Common side effects

  • Headache, especially when starting
  • Dizziness or light-headedness
  • Flushing
  • Low blood pressure
  • Fast heartbeat

Serious effects — get help

  • Fainting or severe dizziness
  • A very fast or irregular heartbeat
  • Worsening or sudden chest pain
  • Signs of a serious allergic reaction

If a reaction is severe — for example trouble breathing, swelling of the face or throat, or collapse — go to the nearest emergency room now or call your local emergency number. Do not wait for an online consultation.

Interactions to watch

  • Erectile-dysfunction medicines such as sildenafil, tadalafil, and vardenafil (dangerous drop in blood pressure — do not combine)
  • Other blood pressure medicines
  • Riociguat (used for lung blood-pressure conditions)
  • Alcohol (added drop in blood pressure)

Who should take care

  • Never take with erectile-dysfunction medicines such as sildenafil — the combination can cause a dangerous fall in blood pressure
  • This is for preventing angina, not for relieving a sudden attack; ask your clinician what to use for that
  • Do not stop suddenly without advice
  • Rise slowly to reduce dizziness
  • Tell your clinician about low blood pressure or recent heart attack

Frequently asked questions

Is this the medicine I put under my tongue for an attack?
No. Isosorbide mononitrate is taken regularly to prevent angina. A different, fast-acting nitrate is used for a sudden attack. Ask your clinician what to use and when.
Why do I need a nitrate-free gap each day?
Using a nitrate continuously can make the body get used to it so it works less well. A daily low-level period helps keep it effective. Follow the schedule your clinician gives you.
Why does it give me a headache?
Headaches are common when starting because the medicine widens blood vessels. They often ease over time; tell your clinician if they are severe.
Can I take it with erectile-dysfunction pills?
No. Combining nitrates with medicines like sildenafil can cause a dangerous drop in blood pressure. Never use them together.
Is Isosorbide mononitrate safe to take?
For most people it is safe when taken exactly as a doctor or pharmacist advises and as printed on the label. Tell your clinician about your other medicines and health conditions, and seek urgent care for any serious reaction.

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