polythiazide and Arsenic trioxide Interactions

Interactions between polythiazide and Arsenic trioxide (arsenic trioxide)

polythiazide and arsenic trioxide (Major Drug-Drug)

MONITOR CLOSELY: Arsenic trioxide can cause QT interval prolongation and complete atrioventricular block. 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 arsenic trioxide 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 arsenic trioxide. 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.