Drug interactions
Clonazepam + Fosamprenavir
Severity: Moderate
Clonazepam and Fosamprenavir: 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 (as amprenavir, usually with ritonavir) inhibits CYP3A4 and may increase clonazepam levels, raising the risk of oversedation and respiratory depression.
What this interaction means in plain words
Clonazepam and Fosamprenavir 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 CYP3A4-mediated clonazepam metabolism.
What to do
Use a lower clonazepam dose and titrate carefully. Monitor for sedation and respiratory depression.
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 Clonazepam
- Calcium / magnesium / potassium / sodium oxybates + Clonazepam Contraindicated
- Clonazepam + Sodium oxybate Contraindicated
- Alfentanil + Clonazepam Major
- Alprazolam + Clonazepam Major
- Amobarbital + Clonazepam Major
- Belladonna and opium + Clonazepam Major
Frequently asked questions
Can I take Clonazepam with Fosamprenavir?
MediHelp rates the interaction as moderate. Clonazepam and Fosamprenavir 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 (as amprenavir, usually with ritonavir) inhibits CYP3A4 and may increase clonazepam levels, raising the risk of oversedation and respiratory depression.
How serious is the interaction between Clonazepam and Fosamprenavir?
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 a lower clonazepam dose and titrate carefully. Monitor for sedation and respiratory depression.
What other medicines interact with Clonazepam?
MediHelp also lists interactions of Clonazepam with, for example, Calcium / magnesium / potassium / sodium oxybates, Sodium oxybate, Alfentanil. The full list is on the Clonazepam page.
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