Drug interactions
Phenelzine + Primidone
Severity: Moderate
Phenelzine and Primidone: 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
MAO inhibitors may increase sedation with primidone, which is metabolized partly to phenobarbital. The interaction is mainly theoretical, though additive CNS depression is plausible.
What this interaction means in plain words
Phenelzine and Primidone 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.
Phenelzine belongs to Central Nervous System; Primidone belongs to Central Nervous System.
Why it happens
Possible reduced metabolism of the barbiturate metabolite with additive CNS depression; not firmly established.
What to do
Monitor for sedation and ataxia, and adjust the primidone dose according to response and serum levels.
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 Phenelzine
- 5-HTP + Phenelzine Contraindicated
- Amitriptyline + Phenelzine Contraindicated
- Amoxapine + Phenelzine Contraindicated
- Atomoxetine + Phenelzine Contraindicated
- Benzphetamine + Phenelzine Contraindicated
- Brimonidine + Phenelzine Contraindicated
Other interactions of Primidone
- Lorlatinib + Primidone Contraindicated
- Lurasidone + Primidone Contraindicated
- Primidone + Ranolazine Contraindicated
- Primidone + Sofosbuvir-velpatasvir-voxilaprevir Contraindicated
- Primidone + Voriconazole Contraindicated
- Abiraterone + Primidone Major
Frequently asked questions
Can I take Phenelzine with Primidone?
MediHelp rates the interaction as moderate. Phenelzine and Primidone 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. MAO inhibitors may increase sedation with primidone, which is metabolized partly to phenobarbital. The interaction is mainly theoretical, though additive CNS depression is plausible.
How serious is the interaction between Phenelzine and Primidone?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor for sedation and ataxia, and adjust the primidone dose according to response and serum levels.
What other medicines interact with Phenelzine?
MediHelp also lists interactions of Phenelzine with, for example, 5-HTP, Amitriptyline, Amoxapine. The full list is on the Phenelzine page.
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