Drug interactions
Montelukast + Phenobarbital
Severity: Minor
Montelukast and Phenobarbital: 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
Phenobarbital induces hepatic enzymes and may lower montelukast plasma concentrations. This could reduce control of asthma or allergic rhinitis, although the clinical effect is usually modest.
What this interaction means in plain words
Montelukast and Phenobarbital have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Why it happens
Phenobarbital induces CYP3A4 and other CYP enzymes involved in montelukast metabolism, increasing its clearance.
What to do
Monitor asthma control when phenobarbital is started or stopped; consider increasing montelukast only if symptoms worsen.
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
Frequently asked questions
Can I take Montelukast with Phenobarbital?
MediHelp rates the interaction as minor. Montelukast and Phenobarbital have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Phenobarbital induces hepatic enzymes and may lower montelukast plasma concentrations. This could reduce control of asthma or allergic rhinitis, although the clinical effect is usually modest.
How serious is the interaction between Montelukast and Phenobarbital?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor asthma control when phenobarbital is started or stopped; consider increasing montelukast only if symptoms worsen.
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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