Drug interactions
Modafinil + Primidone
Severity: Moderate
Modafinil 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, metabolized partly to phenobarbital, induces CYP3A4 and may lower modafinil concentrations. This can reduce wakefulness benefit.
What this interaction means in plain words
Modafinil 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.
Modafinil belongs to Central Nervous System; Primidone belongs to Central Nervous System.
Why it happens
Primidone and phenobarbital induce CYP3A4, increasing modafinil clearance.
What to do
Monitor for reduced modafinil effect and increase the dose if needed; reassess when primidone is stopped.
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 Modafinil
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 Modafinil with Primidone?
MediHelp rates the interaction as moderate. Modafinil 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, metabolized partly to phenobarbital, induces CYP3A4 and may lower modafinil concentrations. This can reduce wakefulness benefit.
How serious is the interaction between Modafinil 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 reduced modafinil effect and increase the dose if needed; reassess when primidone is stopped.
What other medicines interact with Modafinil?
MediHelp also lists interactions of Modafinil with, for example, Lenacapavir, Leniolisib, Lorlatinib. The full list is on the Modafinil page.
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