Drug interactions
Ketoconazole + Montelukast
Severity: Minor
Ketoconazole 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
Ketoconazole strongly inhibits CYP3A4 and may raise montelukast levels slightly. Because montelukast is cleared mainly by CYP2C8, significant effects are not expected.
What this interaction means in plain words
Ketoconazole 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.
Ketoconazole belongs to Anti Fungals; Montelukast belongs to Respiratory.
Why it happens
CYP3A4 inhibition by ketoconazole reduces a minor montelukast metabolic pathway.
What to do
No dose adjustment is needed. Monitor for headache, gastrointestinal upset 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 Ketoconazole
- Alfuzosin + Ketoconazole Contraindicated
- Alprazolam + Ketoconazole Contraindicated
- Avanafil + Ketoconazole Contraindicated
- Conivaptan + Ketoconazole Contraindicated
- Dihydroergotamine intranasal + Ketoconazole Contraindicated
- Dihydroergotamine + Ketoconazole Contraindicated
Frequently asked questions
Can I take Ketoconazole with Montelukast?
MediHelp rates the interaction as minor. Ketoconazole 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. Ketoconazole strongly inhibits CYP3A4 and may raise montelukast levels slightly. Because montelukast is cleared mainly by CYP2C8, significant effects are not expected.
How serious is the interaction between Ketoconazole 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 dose adjustment is needed. Monitor for headache, gastrointestinal upset 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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