Drug interactions
Sulfamethoxazole + Ziprasidone
Severity: Moderate
Sulfamethoxazole and Ziprasidone: 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
Sulfamethoxazole, usually given with trimethoprim, has been linked to QT prolongation and may add to ziprasidone's effect. The risk is higher with electrolyte disturbances, especially hyperkalemia or other cardiac risk factors.
What this interaction means in plain words
Sulfamethoxazole and Ziprasidone 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
Possible additive QT prolongation; the evidence for sulfamethoxazole is limited.
What to do
Consider an alternative antibiotic if the patient has other QT risk factors. Otherwise check ECG and electrolytes during treatment.
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 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 Sulfamethoxazole with Ziprasidone?
MediHelp rates the interaction as moderate. Sulfamethoxazole and Ziprasidone 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. Sulfamethoxazole, usually given with trimethoprim, has been linked to QT prolongation and may add to ziprasidone's effect. The risk is higher with electrolyte disturbances, especially hyperkalemia or other cardiac risk factors.
How serious is the interaction between Sulfamethoxazole and Ziprasidone?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Consider an alternative antibiotic if the patient has other QT risk factors. Otherwise check ECG and electrolytes during treatment.
What other medicines interact with Ziprasidone?
MediHelp also lists interactions of Ziprasidone with, for example, Amiodarone, Amitriptyline, Arsenic trioxide. The full list is on the Ziprasidone page.
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