Drug interactions
Brimonidine + Primidone
Severity: Moderate
Brimonidine 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
Primidone is metabolized to phenobarbital and causes sedation. Systemic brimonidine may add to drowsiness.
What this interaction means in plain words
Brimonidine 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.
Brimonidine belongs to Miscellaneous; Primidone belongs to Central Nervous System.
Why it happens
Additive CNS depression from barbiturate-like GABAergic effects and central alpha-2 agonism.
What to do
Monitor for oversedation and impaired alertness, especially during primidone initiation or titration.
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 Brimonidine
- Brimonidine + Isocarboxazid Contraindicated
- Brimonidine + Linezolid Contraindicated
- Brimonidine + Phenelzine Contraindicated
- Brimonidine + Procarbazine Contraindicated
- Brimonidine + Rasagiline Contraindicated
- Brimonidine + Selegiline 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 Brimonidine with Primidone?
MediHelp rates the interaction as moderate. Brimonidine 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. Primidone is metabolized to phenobarbital and causes sedation. Systemic brimonidine may add to drowsiness.
How serious is the interaction between Brimonidine 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 oversedation and impaired alertness, especially during primidone initiation or titration.
What other medicines interact with Brimonidine?
MediHelp also lists interactions of Brimonidine with, for example, Isocarboxazid, Linezolid, Phenelzine. The full list is on the Brimonidine page.
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