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Arsenic trioxide

APL Differentiation Syndrome; Cardiac Conduction Abnormalities; and Electrolyte Monitoring; Encephalopathy

APL Differentiation Syndrome

  • Differentiation Syndrome: Patients with acute promyelocytic leukemia (APL) treated with TRISENOX have experienced differentiation syndrome, which may be life- threatening or fatal. Signs and symptoms may include unexplained fever, dyspnea, hypoxia, acute respiratory distress, pulmonary infiltrates, pleural or pericardial effusions, weight gain, peripheral edema, hypotension, renal insufficiency, hepatopathy, and multi-organ dysfunction, in the presence or absence of leukocytosis. If differentiation syndrome is suspected, immediately initiate high-dose corticosteroids and hemodynamic monitoring until resolution. Temporarily withhold TRISENOX

Cardiac Conduction Abnormalities

  • Cardiac Conduction Abnormalities: TRISENOX can cause QTc interval prolongation, complete atrioventricular block and torsade de pointes, which can be fatal. Before administering TRISENOX, assess the QTc interval, correct electrolyte abnormalities, and consider discontinuing drugs known to prolong QTc interval. Do not administer TRISENOX to patients with a ventricular arrhythmia or prolonged QTc interval. Withhold TRISENOX until resolution and resume at reduced dose for QTc prolongation


  • Serious encephalopathy, including Wernicke’s, has occurred in patients treated with TRISENOX. 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 TRISENOX. If encephalopathy is suspected, immediately interrupt TRISENOX and initiate parenteral thiamine. Monitor until symptoms resolve or improve and thiamine levels normalize.

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Arsenic Trioxide

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Updated November 2020