Drug interactions
Foscarnet + Itraconazole
Severity: Moderate
Foscarnet 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
Both drugs have been linked to QT prolongation, and foscarnet also causes electrolyte disturbances such as low calcium, magnesium and potassium. These effects together increase arrhythmia risk.
What this interaction means in plain words
Foscarnet 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.
Foscarnet belongs to Anti Virals; Itraconazole belongs to Anti Fungals.
Why it happens
Additive QT prolongation, worsened by foscarnet-induced electrolyte depletion.
What to do
Monitor ECG and serum electrolytes and replace deficits promptly.
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
Other interactions of Foscarnet
- Cidofovir + Foscarnet Contraindicated
- Foscarnet + Pimozide Contraindicated
- Foscarnet + Thioridazine Contraindicated
- Foscarnet + Vandetanib Contraindicated
- Adagrasib + Foscarnet Major
- Adefovir + Foscarnet Major
Frequently asked questions
Can I take Foscarnet with Itraconazole?
MediHelp rates the interaction as moderate. Foscarnet 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. Both drugs have been linked to QT prolongation, and foscarnet also causes electrolyte disturbances such as low calcium, magnesium and potassium. These effects together increase arrhythmia risk.
How serious is the interaction between Foscarnet 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: Monitor ECG and serum electrolytes and replace deficits promptly.
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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