bumetanide and Tikosyn Interactions

Interactions between bumetanide and Tikosyn (dofetilide)

bumetanide and dofetilide (Major Drug-Drug)

MONITOR CLOSELY: Dofetilide can cause dose- and concentration-related QT interval prolongation. Theoretically, coadministration with agents that can produce hypokalemia and/or hypomagnesemia (e.g., potassium-wasting diuretics, amphotericin B, cation exchange resins, stimulant laxatives) may result in elevated risk of ventricular arrhythmias, including ventricular tachycardia and torsade de pointes, because of additive arrhythmogenic potential.

MANAGEMENT: Caution is advised if dofetilide must be used concomitantly with medications that can cause potassium and/or magnesium disturbances. Serum electrolytes should be evaluated and any abnormalities corrected prior to initiating therapy with dofetilide. During therapy, potassium concentrations should be kept above 4 mEq/dL and magnesium concentrations above 1.8 mg/dL. Patients should also have frequent ECGs and be monitored for serious arrhythmias when QT intervals are prolonged. Patients should be advised to seek medical attention if they experience symptoms that could indicate the occurrence of torsade de pointes such as dizziness, palpitations, or syncope.