Drug interactions
Posaconazole + Tolvaptan
Severity: Contraindicated
Posaconazole and Tolvaptan: 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
Posaconazole greatly increases tolvaptan exposure, which can cause excessively rapid sodium correction, dehydration and hypernatremia.
What this interaction means in plain words
Posaconazole and Tolvaptan 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.
Posaconazole belongs to Anti Fungals; Tolvaptan belongs to Endocrine.
Why it happens
Strong CYP3A4 inhibition reduces tolvaptan clearance.
What to do
Avoid the combination; tolvaptan labeling contraindicates strong CYP3A inhibitors. Use an alternative antifungal or treat hyponatremia differently.
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 Posaconazole
- Artemether + Posaconazole Contraindicated
- Avanafil + Posaconazole Contraindicated
- Cobimetinib + Posaconazole Contraindicated
- Conivaptan + Posaconazole Contraindicated
- Dihydroergotamine intranasal + Posaconazole Contraindicated
- Dihydroergotamine + Posaconazole Contraindicated
Other interactions of Tolvaptan
- Atazanavir + Tolvaptan Contraindicated
- Ceritinib + Tolvaptan Contraindicated
- Cobicistat + Tolvaptan Contraindicated
- Conivaptan + Tolvaptan Contraindicated
- Darunavir + Tolvaptan Contraindicated
- Idelalisib + Tolvaptan Contraindicated
Frequently asked questions
Can I take Posaconazole with Tolvaptan?
MediHelp rates the interaction as contraindicated. Posaconazole and Tolvaptan 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. Posaconazole greatly increases tolvaptan exposure, which can cause excessively rapid sodium correction, dehydration and hypernatremia.
How serious is the interaction between Posaconazole and Tolvaptan?
MediHelp rates it contraindicated, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination; tolvaptan labeling contraindicates strong CYP3A inhibitors. Use an alternative antifungal or treat hyponatremia differently.
What other medicines interact with Posaconazole?
MediHelp also lists interactions of Posaconazole with, for example, Artemether, Avanafil, Cobimetinib. The full list is on the Posaconazole page.
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