MajorClass III antiarrhythmic×Antifungals, triazole derivatives
Updated · Methodology
Mechanism
Dual mechanism. Fluconazole blocks CYP3A4 (the main dronedarone clearance route) and prolongs QT itself. Dronedarone plasma levels rise; QT effects add up.
Symptoms
QT prolongation on ECG. Dizziness, syncope, palpitations. Severe cases: polymorphic ventricular tachycardia (torsades de pointes). Risk is higher with hypokalaemia and hypomagnesaemia.
Management
Avoid the combination. Alternative antifungals: echinocandins (micafungin, caspofungin) for systemic mycoses or terbinafine for dermatophytosis. If fluconazole is needed: ECG before start and every 3 days during therapy.
Check the full regimen, not just this pair
Opens the checker with these two drugs prefilled. Add the rest of the regimen and recompute additive risks.
Summary of a multi-drug list →
Medicine list: everything you take in one place →
Sources
- FDA: Multaq (dronedarone) prescribing information (2020)– ; DailyMed setid 7fa41601-7fb5-4155-8e50-2ae903f0d2d6
- AEMPS: Ficha técnica: Dronedarona (nº registro 84320), sección 4.5 (2025)– AEMPS, CIMA, nº registro 84320, revisión 10/2025, sección 4.5