Acute methemoglobinemia after endoscopy.

Acute methemoglobinemia may be caused by topical anesthetics and other oxidizing medications commonly prescribed by Family Physicians. Without knowledge of this potentially lethal condition, delay in diagnosis and treatment is likely. Methemoglobinemia should be considered in any patient presenting with cyanosis, particularly after the use of oxidizing medications. We describe a case of methemoglobinemia in a patient who presented with cyanosis after endoscopy. This case followed otherwise uncomplicated upper gastrointestinal (GI) endoscopy. The diagnosis was delayed several hours because the physicians treating the patient did not consider the possibility of acute methemoglobinemia.