Drug interactions
Dofetilide + Triamterene
Severity: Major
Dofetilide and Triamterene: 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
Dofetilide is eliminated partly by renal cationic secretion, and triamterene is a cationic drug that can compete for this pathway. Higher dofetilide levels increase the risk of QT prolongation and torsades de pointes. Triamterene-related electrolyte disturbances may also add to proarrhythmic risk.
What this interaction means in plain words
Dofetilide and Triamterene 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.
Dofetilide belongs to Cardiovascular; Triamterene belongs to Cardiovascular.
Why it happens
Competition for renal tubular cationic secretion raises dofetilide exposure, with additive QT risk if electrolytes are abnormal.
What to do
Avoid if possible, particularly with reduced renal function; if combined, monitor QTc, creatinine clearance, potassium, and magnesium closely and adjust dofetilide dosing per labeling.
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 Triamterene
- Amiloride + Triamterene Contraindicated
- Eplerenone + Triamterene Contraindicated
- Potassium citrate / citric acid + Triamterene Contraindicated
- Potassium citrate + Triamterene Contraindicated
- Spironolactone + Triamterene Contraindicated
- Aceclofenac + Triamterene Major
Other interactions of Dofetilide
- Amiodarone + Dofetilide Contraindicated
- Amisulpride + Dofetilide Contraindicated
- Amlodipine-hydrochlorothiazide-valsartan + Dofetilide Contraindicated
- Amlodipine-olmesartan-hydrochlorothiazide + Dofetilide Contraindicated
- Candesartan-hydrochlorothiazide + Dofetilide Contraindicated
- Captopril-hydrochlorothiazide + Dofetilide Contraindicated
Frequently asked questions
Can I take Dofetilide with Triamterene?
MediHelp rates the interaction as major. Dofetilide and Triamterene 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. Dofetilide is eliminated partly by renal cationic secretion, and triamterene is a cationic drug that can compete for this pathway. Higher dofetilide levels increase the risk of QT prolongation and torsades de pointes. Triamterene-related electrolyte disturbances may also add to proarrhythmic risk.
How serious is the interaction between Dofetilide and Triamterene?
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 if possible, particularly with reduced renal function; if combined, monitor QTc, creatinine clearance, potassium, and magnesium closely and adjust dofetilide dosing per labeling.
What other medicines interact with Triamterene?
MediHelp also lists interactions of Triamterene with, for example, Amiloride, Eplerenone, Potassium citrate / citric acid. The full list is on the Triamterene page.
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