It is hard to determine if the severity of our patient’s illness was due to underlying G6PD deficiency in the setting of COVID-19 infection, or if the administration of hydroxychloroquine was likely the precipitating cause of the DAT-negative, acute, severe hemolytic crisis and the resultant methemoglobinemia with subsequent, refractory hypoxemia in a G6PD-deficient patient. Here, G6PD is linked to G6PD deficiency.