Drug interactions
Efavirenz + Montelukast
Severity: Minor
Efavirenz and Montelukast: 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
Efavirenz induces CYP3A4 and CYP2B6 and may lower montelukast exposure somewhat. Because montelukast has a wide therapeutic margin, the effect is usually minor.
What this interaction means in plain words
Efavirenz and Montelukast have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Efavirenz belongs to Anti Virals; Montelukast belongs to Respiratory.
Why it happens
Efavirenz induction of hepatic CYP enzymes increases montelukast clearance.
What to do
No routine dose change is needed. Reassess symptom control if asthma worsens.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Efavirenz and Montelukast, 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
Try Pro+ free for 14 days on the web. No card needed.
Other interactions of Montelukast
- Apalutamide + Montelukast Moderate
- Carbamazepine + Montelukast Moderate
- Deferasirox + Montelukast Moderate
- Enzalutamide + Montelukast Moderate
- Fosphenytoin + Montelukast Moderate
- Gemfibrozil + Montelukast Moderate
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 Montelukast?
MediHelp rates the interaction as minor. Efavirenz and Montelukast have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Efavirenz induces CYP3A4 and CYP2B6 and may lower montelukast exposure somewhat. Because montelukast has a wide therapeutic margin, the effect is usually minor.
How serious is the interaction between Efavirenz and Montelukast?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: No routine dose change is needed. Reassess symptom control if asthma worsens.
What other medicines interact with Montelukast?
MediHelp also lists interactions of Montelukast with, for example, Apalutamide, Carbamazepine, Deferasirox. The full list is on the Montelukast 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.
