Drug interactions
Isosorbide mononitrate + Nitroglycerin rectal
Severity: Moderate
Isosorbide mononitrate and Nitroglycerin rectal: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Both agents are organic nitrates, so combining them adds vasodilatory effects. This can cause hypotension, dizziness and headache. Rectal nitroglycerin is typically used for anal fissure, but absorption is still systemic.
What this interaction means in plain words
Isosorbide mononitrate and Nitroglycerin rectal can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Additive nitric oxide-mediated vasodilation.
What to do
Monitor blood pressure and symptoms of hypotension. Consider an alternative fissure treatment such as a topical calcium channel blocker if hypotension occurs.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Isosorbide mononitrate
- Avanafil + Isosorbide mononitrate Contraindicated
- Isosorbide mononitrate + Riociguat Contraindicated
- Isosorbide mononitrate + Sildenafil Contraindicated
- Isosorbide mononitrate + Tadalafil Contraindicated
- Isosorbide mononitrate + Vardenafil Contraindicated
- Ergotamine + Isosorbide mononitrate Major
Frequently asked questions
Can I take Isosorbide mononitrate with Nitroglycerin rectal?
MediHelp rates the interaction as moderate. Isosorbide mononitrate and Nitroglycerin rectal can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Both agents are organic nitrates, so combining them adds vasodilatory effects. This can cause hypotension, dizziness and headache. Rectal nitroglycerin is typically used for anal fissure, but absorption is still systemic.
How serious is the interaction between Isosorbide mononitrate and Nitroglycerin rectal?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor blood pressure and symptoms of hypotension. Consider an alternative fissure treatment such as a topical calcium channel blocker if hypotension occurs.
What other medicines interact with Isosorbide mononitrate?
MediHelp also lists interactions of Isosorbide mononitrate with, for example, Avanafil, Riociguat, Sildenafil. The full list is on the Isosorbide mononitrate page.
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