In glucose-6-phosphate-dehydrogenase deficiency (favism), exposure to oxidant agents can trigger hemolytic crises. The intravenous administration of very high doses vitamin C was proposed as a treatment for severe coronavirus disease 2019 (COVID-19) pneumonia. Unlike low doses, (>6 gr daily) promote H2O2 formation, oxidation hemoglobin methemoglobin and, eventually, anemia in patients with f...