Arsenic trioxide Disease Interactions

Arsenic trioxide can cause QTc interval prolongation, complete atrioventricular block, and a torsade de pointes- type ventricular arrhythmia, which can be fatal. Prior to initiating therapy with arsenic trioxide, assess the QTc interval by electrocardiogram, correct pre- existing electrolyte abnormalities, and consider discontinuing drugs known to prolong QTc interval. Arsenic trioxide should not be administered to patients with ventricular arrhythmia or prolonged QTc interval.

Serious encephalopathy, including Wernicke's, has occurred in patients treated with arsenic trioxide injection. Wernicke's is a neurologic emergency. Consider testing thiamine levels in patients at risk for thiamine deficiency. Administer parenteral thiamine in patients with or at risk for thiamine deficiency. Monitor patients for neurological symptoms and nutritional status while receiving arsenic trioxide injection. If encephalopathy is suspected, immediately interrupt arsenic trioxide injection and initiate parenteral thiamine. Monitor until symptoms resolve or improve and thiamine levels normalize.