Drug interactions
Fosamprenavir + Itraconazole
Severity: Moderate
Fosamprenavir and Itraconazole: 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
Itraconazole and amprenavir (the active form of fosamprenavir) can raise each other's levels through CYP3A4. This may increase adverse effects of either drug, and ritonavir boosting adds further interaction.
What this interaction means in plain words
Fosamprenavir and Itraconazole 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
Mutual CYP3A4 inhibition increases concentrations of both drugs.
What to do
Limit the itraconazole dose to the labeled maximum when given with ritonavir-boosted fosamprenavir. Monitor for itraconazole toxicity and antiretroviral adverse effects, using drug levels if available.
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 Itraconazole
- Alfuzosin + Itraconazole Contraindicated
- Alprazolam + Itraconazole Contraindicated
- Avanafil + Itraconazole Contraindicated
- Conivaptan + Itraconazole Contraindicated
- Dihydroergotamine intranasal + Itraconazole Contraindicated
- Dihydroergotamine + Itraconazole Contraindicated
Frequently asked questions
Can I take Fosamprenavir with Itraconazole?
MediHelp rates the interaction as moderate. Fosamprenavir and Itraconazole 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. Itraconazole and amprenavir (the active form of fosamprenavir) can raise each other's levels through CYP3A4. This may increase adverse effects of either drug, and ritonavir boosting adds further interaction.
How serious is the interaction between Fosamprenavir and Itraconazole?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Limit the itraconazole dose to the labeled maximum when given with ritonavir-boosted fosamprenavir. Monitor for itraconazole toxicity and antiretroviral adverse effects, using drug levels if available.
What other medicines interact with Itraconazole?
MediHelp also lists interactions of Itraconazole with, for example, Alfuzosin, Alprazolam, Avanafil. The full list is on the Itraconazole page.
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