Drug interactions
Mirtazapine + Paroxetine
Severity: Moderate
Mirtazapine and Paroxetine: moderate 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
Combining a serotonergic SSRI with mirtazapine raises the risk of serotonin syndrome, with agitation, tremor, hyperreflexia, sweating and fever. Both drugs also have some QT-prolonging potential, although the clinical effect is usually small. The combination is used deliberately in some resistant depression but needs vigilance.
What this interaction means in plain words
Mirtazapine and Paroxetine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Mirtazapine belongs to Central Nervous System; Paroxetine belongs to Central Nervous System.
Why it happens
Additive serotonergic activity (SSRI reuptake inhibition plus mirtazapine's enhancement of serotonin transmission) with possible additive QT effects.
What to do
Start with low doses and titrate slowly, and educate the patient on early signs of serotonin toxicity. Consider ECG monitoring if other QT-prolonging drugs or risk factors are present.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Paroxetine
- Isocarboxazid + Paroxetine Contraindicated
- Methylene blue + Paroxetine Contraindicated
- Paroxetine + Phenelzine Contraindicated
- Paroxetine + Pimozide Contraindicated
- Paroxetine + Procarbazine Contraindicated
- Paroxetine + Selegiline Contraindicated
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 Mirtazapine with Paroxetine?
MediHelp rates the interaction as moderate. Mirtazapine and Paroxetine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Combining a serotonergic SSRI with mirtazapine raises the risk of serotonin syndrome, with agitation, tremor, hyperreflexia, sweating and fever. Both drugs also have some QT-prolonging potential, although the clinical effect is usually small. The combination is used deliberately in some resistant depression but needs vigilance.
How serious is the interaction between Mirtazapine and Paroxetine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Start with low doses and titrate slowly, and educate the patient on early signs of serotonin toxicity. Consider ECG monitoring if other QT-prolonging drugs or risk factors are present.
What other medicines interact with Paroxetine?
MediHelp also lists interactions of Paroxetine with, for example, Isocarboxazid, Methylene blue, Phenelzine. The full list is on the Paroxetine page.
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