Drug interactions
Efavirenz + Flibanserin
Severity: Major
Efavirenz and Flibanserin: major 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
Efavirenz induces CYP3A4 and may substantially lower flibanserin concentrations, reducing its efficacy. Flibanserin labeling advises against use with strong CYP3A4 inducers.
What this interaction means in plain words
Efavirenz and Flibanserin 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.
Efavirenz belongs to Anti Virals; Flibanserin belongs to Genitourinary.
Why it happens
Efavirenz induces CYP3A4, increasing flibanserin metabolism.
What to do
Avoid concurrent use. If antiretroviral therapy is needed, consider whether flibanserin remains appropriate.
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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Other interactions of Flibanserin
- Atazanavir + Flibanserin Contraindicated
- Ceritinib + Flibanserin Contraindicated
- Clarithromycin + Flibanserin Contraindicated
- Cobicistat + Flibanserin Contraindicated
- Conivaptan + Flibanserin Contraindicated
- Crizotinib + Flibanserin Contraindicated
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 Efavirenz with Flibanserin?
MediHelp rates the interaction as major. Efavirenz and Flibanserin 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. Efavirenz induces CYP3A4 and may substantially lower flibanserin concentrations, reducing its efficacy. Flibanserin labeling advises against use with strong CYP3A4 inducers.
How serious is the interaction between Efavirenz and Flibanserin?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid concurrent use. If antiretroviral therapy is needed, consider whether flibanserin remains appropriate.
What other medicines interact with Flibanserin?
MediHelp also lists interactions of Flibanserin with, for example, Atazanavir, Ceritinib, Clarithromycin. The full list is on the Flibanserin page.
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