Drug interactions
Nitroglycerin sublingual + Tadalafil
Severity: Contraindicated
Nitroglycerin sublingual and Tadalafil: contraindicated 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
Tadalafil markedly potentiates the blood pressure lowering effect of nitrates, including sublingual nitroglycerin. The combination can produce profound, refractory hypotension, syncope and myocardial ischemia, and tadalafil's long half-life means the risk persists for days after a dose.
What this interaction means in plain words
Nitroglycerin sublingual and Tadalafil are not normally used together. Taking them at the same time is expected to cause harm or make one of them unsafe, so a different medicine is usually chosen for one of the two.
Why it happens
Nitrates raise cGMP via nitric oxide release while tadalafil blocks cGMP breakdown by PDE5, producing excessive additive vasodilation.
What to do
Do not use together; nitrates must not be given within 48 hours of the last tadalafil dose. If chest pain occurs within that window, seek emergency care and use non-nitrate measures under medical supervision.
What to ask your pharmacist
- Is there an alternative to one of these two medicines for me?
- If both are essential, who is monitoring me and how often?
- Which symptoms mean I should stop and seek help straight away?
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Other interactions of Tadalafil
- Amyl nitrite + Tadalafil Contraindicated
- Isosorbide dinitrate + Tadalafil Contraindicated
- Isosorbide mononitrate + Tadalafil Contraindicated
- Nitroglycerin po + Tadalafil Contraindicated
- Nitroglycerin rectal + Tadalafil Contraindicated
- Nitroglycerin transdermal + Tadalafil Contraindicated
Frequently asked questions
Can I take Nitroglycerin sublingual with Tadalafil?
MediHelp rates the interaction as contraindicated. Nitroglycerin sublingual and Tadalafil are not normally used together. Taking them at the same time is expected to cause harm or make one of them unsafe, so a different medicine is usually chosen for one of the two. Tadalafil markedly potentiates the blood pressure lowering effect of nitrates, including sublingual nitroglycerin. The combination can produce profound, refractory hypotension, syncope and myocardial ischemia, and tadalafil's long half-life means the risk persists for days after a dose.
How serious is the interaction between Nitroglycerin sublingual and Tadalafil?
MediHelp rates it contraindicated, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Do not use together; nitrates must not be given within 48 hours of the last tadalafil dose. If chest pain occurs within that window, seek emergency care and use non-nitrate measures under medical supervision.
What other medicines interact with Tadalafil?
MediHelp also lists interactions of Tadalafil with, for example, Amyl nitrite, Isosorbide dinitrate, Isosorbide mononitrate. The full list is on the Tadalafil page.
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