Methemoglobinemia: pathogenesis, diagnosis, and management.

The diagnosis of methemoglobinemia should be considered in patients presenting with cyanosis and hypoxia. A variety of frequently used medications are capable of inducing methemoglobinemia, with dapsone and benzocaine being common culprits. Unique features, such as a saturation gap and chocolate-brown-colored blood, can raise suspicion for methemoglobinemia.