Drug interactions
Maprotiline + Sulfamethoxazole
Severity: Moderate
Maprotiline and Sulfamethoxazole: 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
Maprotiline can prolong the QT interval, and sulfamethoxazole (usually given with trimethoprim) has been linked to rare QT prolongation and arrhythmia reports. Using both could add to the risk of ventricular arrhythmia, especially with other risk factors.
What this interaction means in plain words
Maprotiline and Sulfamethoxazole 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
Additive pharmacodynamic effect on cardiac repolarization (QT prolongation).
What to do
Obtain a baseline ECG and correct potassium and magnesium before combining. Monitor the QTc and avoid the combination in patients with congenital long QT or other QT-prolonging drugs.
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 Maprotiline
- Arsenic trioxide + Maprotiline Contraindicated
- Disopyramide + Maprotiline Contraindicated
- Dofetilide + Maprotiline Contraindicated
- Ibutilide + Maprotiline Contraindicated
- Isocarboxazid + Maprotiline Contraindicated
- Maprotiline + Methylene blue Contraindicated
Frequently asked questions
Can I take Maprotiline with Sulfamethoxazole?
MediHelp rates the interaction as moderate. Maprotiline and Sulfamethoxazole 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. Maprotiline can prolong the QT interval, and sulfamethoxazole (usually given with trimethoprim) has been linked to rare QT prolongation and arrhythmia reports. Using both could add to the risk of ventricular arrhythmia, especially with other risk factors.
How serious is the interaction between Maprotiline and Sulfamethoxazole?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Obtain a baseline ECG and correct potassium and magnesium before combining. Monitor the QTc and avoid the combination in patients with congenital long QT or other QT-prolonging drugs.
What other medicines interact with Maprotiline?
MediHelp also lists interactions of Maprotiline with, for example, Arsenic trioxide, Disopyramide, Dofetilide. The full list is on the Maprotiline page.
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