Previously reported cases of hypoxemia secondary to methemoglobinemia usually had measured methemoglobin percentages of around 20% or greater. We report an unusual case of methemoglobinemia secondary to dapsone use in a 66-year-old man with obstructive sleep apnea who presented with dyspnea and hypoxia with a methemoglobin percentage of less than 10%.
MATHEW et al. (Wed,) studied this question.