Drug interactions
Dexamethasone + Primidone
Severity: Moderate
Dexamethasone 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, and its active metabolite phenobarbital, induce hepatic enzymes and can speed up the clearance of dexamethasone. This may reduce corticosteroid effect, leading to loss of disease control or inadequate antiemetic or anti-inflammatory response.
What this interaction means in plain words
Dexamethasone 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.
Dexamethasone belongs to Endocrine; Primidone belongs to Central Nervous System.
Why it happens
Induction of CYP3A4 by primidone/phenobarbital increases the metabolic clearance of dexamethasone.
What to do
Monitor clinical response to dexamethasone and increase the dose if the effect is inadequate. Reassess the dose if primidone is stopped or changed.
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 Dexamethasone
- Bcg vaccine live + Dexamethasone Contraindicated
- Dexamethasone + Mifepristone Contraindicated
- Dexamethasone + Rilpivirine Contraindicated
- Dexamethasone + Smallpox vaccine live Contraindicated
- Dexamethasone + Varicella virus vaccine live Contraindicated
- Dexamethasone + Yellow fever vaccine 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 Dexamethasone with Primidone?
MediHelp rates the interaction as moderate. Dexamethasone 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, and its active metabolite phenobarbital, induce hepatic enzymes and can speed up the clearance of dexamethasone. This may reduce corticosteroid effect, leading to loss of disease control or inadequate antiemetic or anti-inflammatory response.
How serious is the interaction between Dexamethasone 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 clinical response to dexamethasone and increase the dose if the effect is inadequate. Reassess the dose if primidone is stopped or changed.
What other medicines interact with Dexamethasone?
MediHelp also lists interactions of Dexamethasone with, for example, Bcg vaccine live, Mifepristone, Rilpivirine. The full list is on the Dexamethasone page.
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