A Guide to G6PD Deficiency

JANUARY 05, 2018
Glucose-6-phosphate dehydrogenase (G6PD) is an enzyme involved in the pentose phosphate pathway and maintaining levels of co-enzyme nicotinamide adenine dinucleotide phosphate (NADPH). NADPH in turn maintains appropriate levels of glutathione, responsible for protecting red blood cells from oxidative damage1.

Those who suffer from the X-linked deficiency are predisposed to hemolytic anemia, because of the breakdown of red blood cells when cells are exposed to oxidative stress. The severity of the condition depends on the enzyme variant2
·       Severe (I): chronic non-spherocytic hemolytic anemia3
·       Severe (II): less than 10% of normal enzyme activity
·       Moderate (III): 10% to 60% of normal enzyme activity
·       Mild to none (IV): 60% to 150% of normal enzyme activity
·       None (V): greater than 150% of normal enzyme activity
Hemolysis can occur after to exposure to certain bacterial or viral infection, drugs, or foods. Individuals of Mediterranean descent have very low levels of G6PD activity, while African-Americans possess 5% to 15% of normal G6PD activity.
Drugs and foods associated with oxidative hemolysis include ascorbic acid; aspirin; dapsone; dimercaprol; fava beans; methylthioninium chloride-methylene blue; nitrofurantoin; prilocaine; primaquine; quinolones; and sulfonamides, including bactrim.

Exams may be done to diagnose and manage G6PD deficiency, including a complete blood count and G6PD enzyme activity. Avoiding drugs or foods associated with hemolysis is essential for those with G6PD deficiency. Individuals are advised to carry a G6PD deficiency alert bracelet. Treatment for severe episodes upon exposure may include blood transfusions.


1. Luzzatto L, Nannelli C, Notaro R. Glucose-6-phosphate dehydrogenase deficiency. Hematol Oncol Clin North Am. 2016;30(2):373-93. doi: 10.1016/j.hoc.2015.11.006. 
2. Frank JE; Diagnosis and management of G6PD deficiency. Am Fam Physician. 2005;72(7):1277-82
3. Gallegher PG. Hemolytic anemias: red cell membrane and metabolic defects: In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 24th ed. Philadelphia, PA: Elsevier Saunders; 2016:164.

Dewilka Simons, PharmD Candidate
Dewilka Simons is a PharmD 2019 candidate at Temple University School of Pharmacy and graduated from the Pennsylvania State University with a BS in Biological Sciences. She is involved in numerous Pharmacy organizations as well as interprofessional organizations that focus on collaborations with various health disciplines. Pharmacy Interests: Solid Organ Transplant, interdisciplinary health approach, patient education, pharmacist treatment perspective, management of adverse effects, challenges/opportunities for Pharmacists outside of the community setting.