Drug interactions
Efavirenz + Felodipine
Severity: Moderate
Efavirenz and Felodipine: 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
Efavirenz induces CYP3A4, which can lower felodipine plasma concentrations. This may reduce blood pressure control or antianginal effect.
What this interaction means in plain words
Efavirenz and Felodipine 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.
Efavirenz belongs to Anti Virals; Felodipine belongs to Cardiovascular.
Why it happens
Efavirenz induces intestinal and hepatic CYP3A4, increasing felodipine first-pass and systemic metabolism.
What to do
Monitor blood pressure and heart rate after starting or stopping efavirenz. Titrate the felodipine dose upward 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
Other interactions of Felodipine
- Felodipine + Itraconazole Contraindicated
- Aldesleukin + Felodipine Major
- Amifostine + Felodipine Major
- Apalutamide + Felodipine Major
- Atazanavir + Felodipine Major
- Carbamazepine + Felodipine Major
Frequently asked questions
Can I take Efavirenz with Felodipine?
MediHelp rates the interaction as moderate. Efavirenz and Felodipine 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. Efavirenz induces CYP3A4, which can lower felodipine plasma concentrations. This may reduce blood pressure control or antianginal effect.
How serious is the interaction between Efavirenz and Felodipine?
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 blood pressure and heart rate after starting or stopping efavirenz. Titrate the felodipine dose upward 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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