Case: We report a case of simultaneous methemoglobinemia and hemolytic anemia, probably related to the use of rasburicase, in a child starting treatment for acute lymphoblastic leukemia (ALL). In addition, the patient developed symptoms of pancreatitis. All complications resolved after 3 days of supportive therapy.
Conclusion: Although usually well tolerated in pediatrics, physicians prescribing rasburicase should be aware of these possible life-threatening adverse reactions.