Skip to content
MediHelp
MediHelp Drug reference

Drug interactions

Efavirenz + Sofosbuvir-velpatasvir-voxilaprevir

Severity: Major

Efavirenz and Sofosbuvir-velpatasvir-voxilaprevir: 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, CYP2B6 and CYP2C8 and lowers velpatasvir and voxilaprevir exposure. This may lead to treatment failure, and labeling does not recommend the combination.

What this interaction means in plain words

Efavirenz and Sofosbuvir-velpatasvir-voxilaprevir 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; Sofosbuvir-velpatasvir-voxilaprevir belongs to Anti Virals.

Evidence level: High

Why it happens

Efavirenz induces CYP3A4, CYP2B6 and CYP2C8, increasing clearance of velpatasvir and voxilaprevir.

What to do

Avoid the combination and switch to a non-inducing antiretroviral regimen with HIV specialist input. If it cannot be changed, use another HCV regimen suited to efavirenz.

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?

Bring a full list of your medicines, including over-the-counter products, supplements and herbal remedies, to every pharmacy visit.

Pro+ members

Unlock the full page

Create an account and start a Pro+ trial to unlock the full management advice for Efavirenz and Sofosbuvir-velpatasvir-voxilaprevir, the additional notes, the evidence detail and the whole-prescription interaction checker.

  • Full clinical management advice
  • Additional notes
  • Evidence detail
  • Interaction checker for a whole prescription
Create free account Sign in

Try Pro+ free for 14 days on the web. No card needed.

Frequently asked questions

Can I take Efavirenz with Sofosbuvir-velpatasvir-voxilaprevir?

MediHelp rates the interaction as major. Efavirenz and Sofosbuvir-velpatasvir-voxilaprevir 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, CYP2B6 and CYP2C8 and lowers velpatasvir and voxilaprevir exposure. This may lead to treatment failure, and labeling does not recommend the combination.

How serious is the interaction between Efavirenz and Sofosbuvir-velpatasvir-voxilaprevir?

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 the combination and switch to a non-inducing antiretroviral regimen with HIV specialist input. If it cannot be changed, use another HCV regimen suited to efavirenz.

What other medicines interact with Sofosbuvir-velpatasvir-voxilaprevir?

MediHelp also lists interactions of Sofosbuvir-velpatasvir-voxilaprevir with, for example, Fosphenytoin, Phenobarbital, Phenytoin. The full list is on the Sofosbuvir-velpatasvir-voxilaprevir page.

Full monographs, dosing and an interaction checker in the MediHelp app

Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.

Download on theApp Store Get it onGoogle Play

Browse A–Z · Drug interactions

Get the app Sign in