High-dose Vitamin C therapy in Methemoglobinemia

ABSTRACT

Methylene blue is the first choice antidote for management of methemoglobinemia, however, some patients are refractory to methylene blue and in most cases, methylene blue cannot be available instantly in Korean emergency departments because of import suspension. A 69-year-old woman visited our emergency department for tachypnea and cyanosis after ingesting 30 tablets of dapsone. Because methylene blue was not available, we intravenously administrated 10 g of vitamin C for symptomatic methemoglobinemia. Repeated i.v. administrations of 10 g of vitamin C in patient without preexisting renal insufficiency successfully treated dapsone-induced methemoglobinemia without causing renal complications. Thus, we recommend that if methylene blue is unavailable or methemoglobinemia is refractory to methylene blue, repeated administrations of 10 g of vitamin C may be considered for the treatment of methemoglobinemia in patients without renal insufficiency.