Glucose-6-Phosphate Dehydrogenase (G6PD) Deficiency By Evan M Braunstein, MD, PhD, Johns Hopkins University School of Medicine Reviewed / Revised Jun 2022 | Modified Sep 2022 View Patient Education Pathophysiology Symptoms and Signs Diagnosis Treatment Key Points Topic Resources Hereditary Erythrocyte G6PD.. Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked enzymatic defect common in people with African ancestry that can result in hemolysis after acute illnesses or intake of oxidant drugs (including salicylates and sulfonamides).