Drug interactions
Isoniazid + Mirtazapine
Severity: Minor
Isoniazid and Mirtazapine: 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
Mirtazapine is partly metabolized by CYP3A4, so isoniazid may modestly increase its levels, causing more sedation. Isoniazid's weak MAO inhibition adds a theoretical serotonergic risk.
What this interaction means in plain words
Isoniazid and Mirtazapine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Isoniazid belongs to Anti Bacterial; Mirtazapine belongs to Central Nervous System.
Why it happens
Isoniazid inhibits CYP3A4 and weakly inhibits MAO.
What to do
Monitor for excess sedation, and for signs of serotonin toxicity. Reduce the mirtazapine dose if needed.
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 Isoniazid
Other interactions of Mirtazapine
- Isocarboxazid + Mirtazapine Contraindicated
- Mirtazapine + Phenelzine Contraindicated
- Mirtazapine + Pimozide Contraindicated
- Mirtazapine + Procarbazine Contraindicated
- Mirtazapine + Rasagiline Contraindicated
- Mirtazapine + Selegiline Contraindicated
Frequently asked questions
Can I take Isoniazid with Mirtazapine?
MediHelp rates the interaction as minor. Isoniazid and Mirtazapine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Mirtazapine is partly metabolized by CYP3A4, so isoniazid may modestly increase its levels, causing more sedation. Isoniazid's weak MAO inhibition adds a theoretical serotonergic risk.
How serious is the interaction between Isoniazid and Mirtazapine?
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 for excess sedation, and for signs of serotonin toxicity. Reduce the mirtazapine dose if needed.
What other medicines interact with Isoniazid?
MediHelp also lists interactions of Isoniazid with, for example, Bacillus calmette-guerin substrain tice, Benzhydrocodone / acetaminophen, Carbamazepine. The full list is on the Isoniazid page.
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