From the Guidelines
Glucose-6-phosphate dehydrogenase (G6PD) screening is strongly recommended before prescribing certain medications that can trigger hemolytic anemia in individuals with G6PD deficiency, as stated in the 2014 guidelines by the HIV Medicine Association of the Infectious Diseases Society of America 1. This recommendation is based on moderate quality evidence and is crucial for preventing potentially life-threatening hemolytic episodes. The following points highlight the importance of G6PD screening:
- G6PD deficiency is an X-linked genetic disorder affecting approximately 400 million people worldwide, with higher prevalence in certain ethnic groups such as Mediterranean, African, Middle Eastern, or Asian descent.
- The enzyme deficiency prevents red blood cells from handling oxidative stress, leading to hemolysis when exposed to certain drugs or foods.
- Medications that can trigger hemolysis in G6PD-deficient individuals include antimalarials (primaquine, chloroquine), antibiotics (sulfonamides, nitrofurantoin), rasburicase, and certain analgesics.
- A recent study published in 2024 emphasizes the importance of G6PD screening before administering primaquine or tafenoquine for the treatment of malaria, as these medications can cause hemolytic anemia in G6PD-deficient individuals 1.
- The screening test requires a small blood sample and results are typically available within a few days, making it a relatively simple and non-invasive procedure.
- By identifying at-risk patients before administering problematic medications, G6PD screening can help prevent serious hemolytic episodes and improve patient outcomes.
From the FDA Drug Label
G6PD testing has to be performed before using primaquine. Due to the limitations of G6PD tests, physicians need to be aware of residual risk of hemolysis and adequate medical support and follow-up to manage hemolytic risk should be available When the G6PD status is unknown and G6PD testing is not available, a decision to prescribe primaquine must be based on an assessment of the risks and benefits of using primaquine.
A Glucose-6-phosphate dehydrogenase (G6PD) screen is required before using primaquine to assess the risk of hemolytic anemia. The decision to prescribe primaquine should be based on an assessment of the risks and benefits if the G6PD status is unknown or testing is not available 2.
From the Research
Glucose-6-phosphate Dehydrogenase Deficiency
- Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common human enzymopathy caused by inherited mutations of the X-linked gene G6PD 3.
- It is estimated that over 400 million people worldwide have G6PD deficiency, with the majority being asymptomatic throughout their lifetime 3, 4, 5.
- G6PD deficiency can lead to acute hemolytic anemia, which can be triggered by ingestion of fava beans, certain drugs, or infection 3, 6.
Screening and Diagnosis
- Reliable diagnostic procedures are available for G6PD deficiency, including point-of-care tests 3.
- Mandatory universal screening for G6PD deficiency can identify at-risk infants and foster early identification, diagnosis, and treatment to eliminate neurotoxicity 7.
- Screening programs for G6PD deficiency are undertaken in communities with a high prevalence of the disorder 5.
Management and Treatment
- Currently, there are no therapeutics for G6PD deficiency, and management is focused on preventing hemolysis by avoiding oxidative stress 4, 5.
- Treatment strategies for G6PD deficiency have been attempted over the years, but potential pharmacological pathways, such as glutathione metabolism and transcriptional upregulation of the G6PD gene, are being explored 4.
- Early identification and treatment of G6PD deficiency can prevent severe hyperbilirubinemia and bilirubin-induced neurologic dysfunction 7.