Drug interactions
Montelukast + Ritonavir
Severity: Minor
Montelukast and Ritonavir: 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
Ritonavir inhibits CYP3A4 and may increase montelukast exposure. Because montelukast is tolerated over a broad dose range, significant toxicity is unlikely.
What this interaction means in plain words
Montelukast and Ritonavir have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Montelukast belongs to Respiratory; Ritonavir belongs to Anti Virals.
Why it happens
Ritonavir inhibits CYP3A4, one pathway of montelukast metabolism (CYP2C8 is the main route).
What to do
No routine dose change; monitor for adverse effects such as headache, abdominal pain or mood changes.
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?
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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 Ritonavir
- Alfuzosin + Ritonavir Contraindicated
- Amiodarone + Ritonavir Contraindicated
- Avanafil + Ritonavir Contraindicated
- Colchicine + Ritonavir Contraindicated
- Dronedarone + Ritonavir Contraindicated
- Eletriptan + Ritonavir Contraindicated
Frequently asked questions
Can I take Montelukast with Ritonavir?
MediHelp rates the interaction as minor. Montelukast and Ritonavir have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Ritonavir inhibits CYP3A4 and may increase montelukast exposure. Because montelukast is tolerated over a broad dose range, significant toxicity is unlikely.
How serious is the interaction between Montelukast and Ritonavir?
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; monitor for adverse effects such as headache, abdominal pain or mood changes.
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.
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