Drug interactions
Paracetamol + Primidone
Severity: Moderate
Paracetamol 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 induces hepatic enzymes, which can lower paracetamol exposure and increase formation of hepatotoxic metabolites. The risk is greatest with high or prolonged paracetamol dosing.
What this interaction means in plain words
Paracetamol 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.
Paracetamol belongs to Musculoskeletal; Primidone belongs to Central Nervous System.
Why it happens
Enzyme induction by primidone and its phenobarbital metabolite increases oxidative metabolism of paracetamol to NAPQI.
What to do
Use the lowest effective paracetamol dose and limit duration. Monitor liver tests if long-term use is needed.
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 Paracetamol
- Ethanol + Paracetamol Major
- Busulfan + Paracetamol Moderate
- Carbamazepine + Paracetamol Moderate
- Cholestyramine + Paracetamol Moderate
- Felbamate + Paracetamol Moderate
- Fosphenytoin + Paracetamol Moderate
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 Paracetamol with Primidone?
MediHelp rates the interaction as moderate. Paracetamol 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 induces hepatic enzymes, which can lower paracetamol exposure and increase formation of hepatotoxic metabolites. The risk is greatest with high or prolonged paracetamol dosing.
How serious is the interaction between Paracetamol 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: Use the lowest effective paracetamol dose and limit duration. Monitor liver tests if long-term use is needed.
What other medicines interact with Paracetamol?
MediHelp also lists interactions of Paracetamol with, for example, Ethanol, Busulfan, Carbamazepine. The full list is on the Paracetamol page.
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