Drug interactions
Fosamprenavir + Nortriptyline
Severity: Moderate
Fosamprenavir and Nortriptyline: 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
Fosamprenavir, particularly when boosted with ritonavir, can raise nortriptyline concentrations, increasing anticholinergic effects, sedation and arrhythmia risk. The effect on tricyclic exposure is variable.
What this interaction means in plain words
Fosamprenavir and Nortriptyline 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.
Why it happens
Inhibition of CYP2D6 and CYP3A4 metabolism of nortriptyline by amprenavir and ritonavir.
What to do
Start nortriptyline at a low dose and titrate to clinical response. Consider tricyclic plasma levels and ECG monitoring.
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
Frequently asked questions
Can I take Fosamprenavir with Nortriptyline?
MediHelp rates the interaction as moderate. Fosamprenavir and Nortriptyline 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. Fosamprenavir, particularly when boosted with ritonavir, can raise nortriptyline concentrations, increasing anticholinergic effects, sedation and arrhythmia risk. The effect on tricyclic exposure is variable.
How serious is the interaction between Fosamprenavir and Nortriptyline?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Start nortriptyline at a low dose and titrate to clinical response. Consider tricyclic plasma levels and ECG monitoring.
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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