Major
Dronedarone × Tramadol
Class III antiarrhythmic×Other opioids
Mechanism
Additive QT risk. Tramadol weakly prolongs QT and blocks serotonin/norepinephrine reuptake. Dronedarone is a potent QT prolonger. Tramadol also lowers seizure threshold.
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. For analgesia on dronedarone, use paracetamol, an NSAID, or morphine/oxycodone (no QT effect).
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.