Isosorbide mononitrate
Isosorbide mononitrate is a nitrate used to prevent angina episodes in some people with coronary disease when prescribed as part of a wider plan. It is not usually the first-line reliever during an acute attack — GTN often fills that role.
This medicine is part of the Blood pressure, cholesterol & related category.
Generic name: isosorbide mononitrate
Quick answers
Short replies to searches people often run before speaking to a clinician. For the overview of what the medicine is used for, see the short summary under the page title above.
What is it for?
Isosorbide mononitrate is a nitrate used to prevent angina episodes in some people with coronary disease when prescribed as part of a wider plan.
How long does it take to work?
Blood pressure can fall over days to weeks after starting or changing dose; attend follow-up checks your GP arranges.
What are common side effects?
Headache, flushing, dizziness, and low blood pressure are common, especially when starting or increasing dose.
Can you take paracetamol or ibuprofen with it?
Ask your GP or pharmacist before taking Isosorbide mononitrate with paracetamol or ibuprofen. Many adults use paracetamol for short periods when appropriate; NSAIDs such as ibuprofen need extra checks with your other medicines and health conditions.
More about what Isosorbide mononitrate is used for
Isosorbide mononitrate is a nitrate used to prevent angina episodes in some people with coronary disease when prescribed as part of a wider plan.
It is not usually the first-line reliever during an acute attack — GTN often fills that role.
How does Isosorbide mononitrate work, and how long does it take to work?
It dilates veins and arteries, reducing heart workload and improving oxygen supply over several hours depending on formulation.
A nitrate-free period each day may be built into dosing to reduce tolerance — follow your specific schedule.
How and when should you take Isosorbide mononitrate?
Tablets may be standard or modified release with different timings. Swallow as your leaflet describes, often away from GTN doses unless advised.
Do not crush modified-release tablets.
What are the common side effects of Isosorbide mononitrate?
Headache, flushing, dizziness, and low blood pressure are common, especially when starting or increasing dose.
Serious side effects of Isosorbide mononitrate — when to get urgent help
Seek urgent help if chest pain is not controlled by your agreed plan, or if you faint.
Do not use with PDE5 inhibitors — dangerous hypotension.
What if you miss a dose of Isosorbide mononitrate?
If you miss a scheduled prevention dose, take it when remembered unless nearly time for the next; do not double.
Who should not take Isosorbide mononitrate?
Hypotension, hypertrophic obstructive cardiomyopathy in some cases, and recent PDE5 inhibitor use are cautions.
Closed-angle glaucoma history — discuss with your prescriber.
Can you take paracetamol or ibuprofen with Isosorbide mononitrate? — other interactions
Sildenafil, Tadalafil, vardenafil, and riociguat are dangerous combinations. Alcohol and other antihypertensives add to dizziness.
Isosorbide mononitrate in pregnancy and breastfeeding
Discuss with your prescriber before use in pregnancy or breastfeeding.
Blood tests and monitoring on Isosorbide mononitrate
Blood pressure and angina symptoms are reviewed when doses change.
What might your GP prescribe instead of Isosorbide mononitrate?
Beta-blockers, calcium channel blockers, or procedures such as stenting may be part of the same overall angina plan.
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Frequently asked questions about Isosorbide mononitrate
People also ask — common Google searches
- What is Isosorbide mononitrate used for?
- Isosorbide mononitrate is a nitrate used to prevent angina episodes in some people with coronary disease when prescribed as part of a wider plan. It is not usually the first-line reliever during an acute attack — GTN often fills that role.
- How long does Isosorbide mononitrate take to work?
- Blood pressure can fall over days to weeks after starting or changing dose; attend follow-up checks your GP arranges. Always follow your prescriber’s follow-up plan.
- Can you take Isosorbide mononitrate with paracetamol or ibuprofen?
- Ask your GP or pharmacist before taking Isosorbide mononitrate with Paracetamol or Ibuprofen. Many adults use paracetamol for short periods when appropriate; NSAIDs such as ibuprofen need extra checks with your other medicines and health conditions.
- What are the side effects of Isosorbide mononitrate?
- Headache, flushing, dizziness, and low blood pressure are common, especially when starting or increasing dose. See the sections below for more detail, including serious side effects and when to seek urgent help.
- Why do I need a nitrate-free period?
- Continuous around-the-clock nitrates can become less effective. Many schedules include hours without the tablet so it keeps working — use only the pattern prescribed for you.
- Can I take Viagra with isosorbide mononitrate?
- No — combining these can cause a dangerous drop in blood pressure. Tell all prescribers you take nitrates before any erectile dysfunction treatment.
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