Glucose-6-phosphate dehydrogenase (G6PD) produces reduced nicotinamide adenine dinucleotide phosphate (NADPH), which is required to protect erythrocytes from oxidative stress. Therefore, G6PD-deficient erythrocytes have reduced capacity in handling oxidative stress, and are therefore susceptible to drug induced lysis, clinically manifested as hemolytic anemia (AHA). In addition, oxidation of hemoglobin iron could result in condition called methemoglobinemia. In severe cases, methemoglobinemia might lead to arrhythmias, seizures and even death.1,2
Individuals with G6PD deficiency may have increased risks of adverse reactions to many drugs. The FDA has introduced warnings or precautions on the drug labeling of primaquine, chloroquine, dapsone, rasburicase, avandaryl tablets (glimepiride + rosiglitazone maleate) and glucovance tablets (metformin + glibenclamide).3 Clinical Pharmacogenetics Implementation Consortium (CPIC) provides guidelines for rasburicase therapy based on the G6PD deficiency genotypes.4
Click here for the full CPIC guideline for G6PD genotype and rasburicase therapy.