Efavirenz and Posaconazole Interaction
Drug interaction information between Efavirenz and Posaconazole.
Efavirenz and Posaconazole have a documented moderate interaction in FDA labeling.
FDA drug labeling documents a moderate-severity interaction between Efavirenz and Posaconazole. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.
How They Interact
Efavirenz causes the body to break down posaconazole more quickly, which lowers the amount of medicine available to fight infections.
FDA Label Information
Posaconazole ↓ posaconazole* Avoid concomitant use unless the benefit outweighs the risks.
Efavirenz Also Interacts With
- Clarithromycin moderate
- Sofosbuvir/Velpatasvir moderate
- Atorvastatin minor
- Sertraline minor
- Bupropion minor
Posaconazole Also Interacts With
- Esomeprazole major
- Digoxin major
- Cimetidine major
- Metoclopramide major
- Phenytoin major
Frequently Asked Questions
What SPL severity band is on file for Efavirenz/Emtricitabine/Tenofovir + Posaconazole?
Compiled FDA labeling labels this pair moderate. That is a source-record field, not an individual medication-combination decision.
Which drug in this pair has the larger labeled-interaction portfolio?
Efavirenz has 32 labeled pairs on file vs Posaconazole's 27. In the moderate band specifically: Efavirenz has 3 (also Clarithromycin, Sofosbuvir/Velpatasvir); Posaconazole has 5 (also Lovastatin, Suvorexant, Tacrolimus Topical, Vorapaxar).
What mechanism field is on file for Efavirenz/Emtricitabine/Tenofovir and Posaconazole?
Efavirenz causes the body to break down posaconazole more quickly, which lowers the amount of medicine available to fight infections.
Posaconazole carries more major-labeled pairs than Efavirenz
SPL source-record counts only. This page's band is moderate · classes on file: Efavirenz (NNRTI / NRTI Combination); Posaconazole (Azole Antifungal).
Posaconazole has 5 major-labeled pairs vs Efavirenz's 0. This page itself is in the moderate band, not the major band.
0 major · 3 moderate · 29 minor · 32 total
- Other moderate peers for Efavirenz
- Clarithromycin
- Sofosbuvir/Velpatasvir
5 major · 5 moderate · 17 minor · 27 total
- Other moderate peers for Posaconazole
- Lovastatin
- Suvorexant
- Tacrolimus Topical
- Vorapaxar
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.
Read our methodology - how this data is sourced, computed, and verified.