Can I take Isosorbide mononitrate/carmil/monomil and Vitamin d together?
Drug interaction guide
Originally published 25 Jan 2026
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There is no known interaction between isosorbide mononitrate (also known by brand names like Carmil or Monomil) and Vitamin D supplements.
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Why this happens
These two substances work in completely different ways in the body. Isosorbide mononitrate relaxes the blood vessels to improve blood flow to the heart, while Vitamin D helps the body absorb calcium and maintain bone health. They do not interfere with each other's absorption, breakdown, or effects.
What you should do
Back to contentsYou can safely take these two medications together. It is usually best to take your heart medication at the same time each day as prescribed by your doctor. If you are taking very high doses of Vitamin D (prescribed for a deficiency), your doctor may monitor your calcium levels, but this is standard practice and not caused by the heart medication.
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Using other medicines
Back to contentsTaking multiple medicines? Our Medicines Interaction Checker helps you check whether your prescriptions, over-the-counter medicines, and supplements are safe to take together. Simply search for your medicines to see potential interactions and what to do about them.
Disclaimer
This information is for general educational purposes only and should not be relied upon as a substitute for professional medical advice. Always consult your GP, pharmacist, or another qualified healthcare professional before making decisions about your medications. Individual circumstances may vary, and only a healthcare professional who knows your medical history can provide personalised guidance.
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Article history
The information on this page is written and peer reviewed by qualified clinicians.
25 Jan 2026 | Originally published

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