Drug interactions
Foscarnet + Ziprasidone
Severity: Major
Foscarnet and Ziprasidone: major 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 can prolong the QT interval, and foscarnet also commonly causes hypocalcemia, hypomagnesemia and hypokalemia that further raise arrhythmia risk. Together they increase the chance of torsades de pointes, particularly in patients with cardiac disease or electrolyte disturbance.
What this interaction means in plain words
Foscarnet and Ziprasidone can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Foscarnet belongs to Anti Virals; Ziprasidone belongs to Central Nervous System.
Why it happens
Additive QT prolongation, compounded by foscarnet-induced electrolyte depletion.
What to do
Avoid the combination where possible, or obtain a baseline ECG and correct calcium, magnesium and potassium before and during therapy. Monitor the QTc and electrolytes regularly and stop ziprasidone if the QTc becomes markedly prolonged.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Foscarnet
- Cidofovir + Foscarnet Contraindicated
- Foscarnet + Pimozide Contraindicated
- Foscarnet + Thioridazine Contraindicated
- Foscarnet + Vandetanib Contraindicated
- Adagrasib + Foscarnet Major
- Adefovir + Foscarnet Major
Other interactions of Ziprasidone
- Amiodarone + Ziprasidone Contraindicated
- Amitriptyline + Ziprasidone Contraindicated
- Arsenic trioxide + Ziprasidone Contraindicated
- Bedaquiline + Ziprasidone Contraindicated
- Chloroquine + Ziprasidone Contraindicated
- Citalopram + Ziprasidone Contraindicated
Frequently asked questions
Can I take Foscarnet with Ziprasidone?
MediHelp rates the interaction as major. Foscarnet and Ziprasidone can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Both drugs can prolong the QT interval, and foscarnet also commonly causes hypocalcemia, hypomagnesemia and hypokalemia that further raise arrhythmia risk. Together they increase the chance of torsades de pointes, particularly in patients with cardiac disease or electrolyte disturbance.
How serious is the interaction between Foscarnet and Ziprasidone?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination where possible, or obtain a baseline ECG and correct calcium, magnesium and potassium before and during therapy. Monitor the QTc and electrolytes regularly and stop ziprasidone if the QTc becomes markedly prolonged.
What other medicines interact with Foscarnet?
MediHelp also lists interactions of Foscarnet with, for example, Cidofovir, Pimozide, Thioridazine. The full list is on the Foscarnet page.
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