Drug interactions
Danazol + Efavirenz
Severity: Minor
Danazol and Efavirenz: 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
Danazol is a CYP3A4 inhibitor and could raise efavirenz concentrations, though efavirenz is also cleared by CYP2B6. Increased CNS adverse effects are possible. Danazol exposure may also fall because efavirenz induces CYP3A4.
What this interaction means in plain words
Danazol and Efavirenz have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Why it happens
Danazol inhibits CYP3A4 while efavirenz induces it, giving bidirectional effects.
What to do
Monitor for efavirenz CNS toxicity and for changes in danazol response.
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 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 Danazol with Efavirenz?
MediHelp rates the interaction as minor. Danazol and Efavirenz have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Danazol is a CYP3A4 inhibitor and could raise efavirenz concentrations, though efavirenz is also cleared by CYP2B6. Increased CNS adverse effects are possible. Danazol exposure may also fall because efavirenz induces CYP3A4.
How serious is the interaction between Danazol and Efavirenz?
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 for efavirenz CNS toxicity and for changes in danazol response.
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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