Drug interactions
Clarithromycin + Tadalafil
Severity: Major
Clarithromycin and Tadalafil: major interaction.
Last updated Sources: US FDA label
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
Clarithromycin is a strong CYP3A4 inhibitor and raises tadalafil exposure, increasing the risk of hypotension, syncope, visual changes and priapism. Labeling recommends dose limits for erectile dysfunction.
What this interaction means in plain words
Clarithromycin and Tadalafil can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Clarithromycin belongs to Anti Bacterial; Tadalafil belongs to Genitourinary.
Why it happens
Inhibition of CYP3A4-mediated tadalafil metabolism.
What to do
For erectile dysfunction, limit tadalafil to 10 mg no more often than every 72 hours, or 2.5 mg daily. Avoid use for pulmonary hypertension or choose a non-interacting antibiotic such as azithromycin.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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References
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 sublingual + Tadalafil Contraindicated
Other interactions of Clarithromycin
- Astemizole + Clarithromycin Contraindicated
- Avanafil + Clarithromycin Contraindicated
- Cisapride + Clarithromycin Contraindicated
- Clarithromycin + Colchicine Contraindicated
- Clarithromycin + Conivaptan Contraindicated
- Clarithromycin + Dihydroergotamine Contraindicated
Frequently asked questions
Can I take Clarithromycin with Tadalafil?
MediHelp rates the interaction as major. Clarithromycin and Tadalafil can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Clarithromycin is a strong CYP3A4 inhibitor and raises tadalafil exposure, increasing the risk of hypotension, syncope, visual changes and priapism. Labeling recommends dose limits for erectile dysfunction.
How serious is the interaction between Clarithromycin and Tadalafil?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: For erectile dysfunction, limit tadalafil to 10 mg no more often than every 72 hours, or 2.5 mg daily. Avoid use for pulmonary hypertension or choose a non-interacting antibiotic such as azithromycin.
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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