Drug interactions
Conivaptan + Efavirenz
Severity: Moderate
Conivaptan and Efavirenz: 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
Conivaptan is a CYP3A4 substrate, and efavirenz may reduce its concentrations and aquaretic effect. Clinical significance is uncertain.
What this interaction means in plain words
Conivaptan and Efavirenz 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
Efavirenz induces CYP3A4, increasing conivaptan metabolism.
What to do
Monitor serum sodium frequently during conivaptan therapy and adjust treatment if the response is inadequate.
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 Efavirenz
- Cobimetinib + Efavirenz Contraindicated
- Dienogest / estradiol valerate + Efavirenz Contraindicated
- Dihydroergotamine intranasal + Efavirenz Contraindicated
- Dihydroergotamine + Efavirenz Contraindicated
- Doravirine + Efavirenz Contraindicated
- Efavirenz + Elbasvir / grazoprevir Contraindicated
Frequently asked questions
Can I take Conivaptan with Efavirenz?
MediHelp rates the interaction as moderate. Conivaptan and Efavirenz 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. Conivaptan is a CYP3A4 substrate, and efavirenz may reduce its concentrations and aquaretic effect. Clinical significance is uncertain.
How serious is the interaction between Conivaptan and Efavirenz?
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 serum sodium frequently during conivaptan therapy and adjust treatment if the response is inadequate.
What other medicines interact with Efavirenz?
MediHelp also lists interactions of Efavirenz with, for example, Cobimetinib, Dienogest / estradiol valerate, Dihydroergotamine intranasal. The full list is on the Efavirenz page.
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