Drug interactions
Nortriptyline + Primidone
Severity: Moderate
Nortriptyline 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 is sedating, so combination with nortriptyline can increase drowsiness and psychomotor impairment. Phenobarbital derived from primidone induces hepatic enzymes and may lower nortriptyline exposure. Tricyclics may also lower the seizure threshold.
What this interaction means in plain words
Nortriptyline 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.
Nortriptyline belongs to Central Nervous System; Primidone belongs to Central Nervous System.
Why it happens
Additive CNS depression plus enzyme induction by primidone and its metabolite phenobarbital.
What to do
Monitor sedation, seizure control and antidepressant response, and consider nortriptyline plasma level monitoring with dose adjustment.
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 Nortriptyline
- Disopyramide + Nortriptyline Contraindicated
- Dofetilide + Nortriptyline Contraindicated
- Dronedarone + Nortriptyline Contraindicated
- Ibutilide + Nortriptyline Contraindicated
- Isocarboxazid + Nortriptyline Contraindicated
- Methylene blue + Nortriptyline 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 Nortriptyline with Primidone?
MediHelp rates the interaction as moderate. Nortriptyline 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 is sedating, so combination with nortriptyline can increase drowsiness and psychomotor impairment. Phenobarbital derived from primidone induces hepatic enzymes and may lower nortriptyline exposure. Tricyclics may also lower the seizure threshold.
How serious is the interaction between Nortriptyline 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 sedation, seizure control and antidepressant response, and consider nortriptyline plasma level monitoring with dose adjustment.
What other medicines interact with Nortriptyline?
MediHelp also lists interactions of Nortriptyline with, for example, Disopyramide, Dofetilide, Dronedarone. The full list is on the Nortriptyline page.
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