Drug interactions
Isosorbide mononitrate + Primidone
Severity: Minor
Isosorbide mononitrate and Primidone: minor 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
Primidone and its metabolite phenobarbital induce hepatic enzymes, which could lower nitrate exposure. Since mononitrate is cleared mostly by non-CYP3A4 pathways, the effect is probably modest. Barbiturates may also add to hypotension.
What this interaction means in plain words
Isosorbide mononitrate and Primidone have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Isosorbide mononitrate belongs to Cardiovascular; Primidone belongs to Central Nervous System.
Why it happens
Enzyme induction by phenobarbital (via primidone), including CYP3A4.
What to do
Monitor anginal control and blood pressure. Increase the nitrate dose only if clinically needed.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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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
Other interactions of Primidone
- Lorlatinib + Primidone Contraindicated
- Lurasidone + Primidone Contraindicated
- Primidone + Ranolazine Contraindicated
- Primidone + Sofosbuvir-velpatasvir-voxilaprevir Contraindicated
- Primidone + Voriconazole Contraindicated
- Abiraterone + Primidone Major
Frequently asked questions
Can I take Isosorbide mononitrate with Primidone?
MediHelp rates the interaction as minor. Isosorbide mononitrate and Primidone have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Primidone and its metabolite phenobarbital induce hepatic enzymes, which could lower nitrate exposure. Since mononitrate is cleared mostly by non-CYP3A4 pathways, the effect is probably modest. Barbiturates may also add to hypotension.
How serious is the interaction between Isosorbide mononitrate and Primidone?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor anginal control and blood pressure. Increase the nitrate dose only if clinically needed.
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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