From the Guidelines
The management of patients with Glucose-6-phosphate dehydrogenase (G6PD) antibodies primarily involves avoiding triggers that can cause hemolytic crises, and screening for G6PD deficiency is recommended before starting therapy with an oxidant drug in patients with a predisposing racial or ethnic background 1.
Management Approach
The approach to managing patients with G6PD deficiency includes:
- Avoiding specific medications known to precipitate hemolysis, such as antimalarials (primaquine, chloroquine), antibiotics (sulfonamides, nitrofurantoin, ciprofloxacin), analgesics (aspirin in high doses), and other drugs like rasburicase and methylene blue 1
- Limiting certain foods, particularly fava beans (which can cause favism), and exercising caution with mothballs (naphthalene)
- Discontinuing the triggering agent, providing supportive care with intravenous fluids to maintain hydration and renal function, monitoring hemoglobin levels, and administering blood transfusions if hemolysis is severe (typically when hemoglobin drops below 7-8 g/dL) during acute hemolytic episodes
- Folate supplementation (1 mg daily) to support red blood cell production
- Patient education, including providing a list of medications to avoid and encouraging medical alert identification
Considerations for Specific Medications
- Methylene blue should be used with caution in patients with G6PD deficiency, as it can induce hemolysis and worsen methemoglobinemia 1
- Dapsone can also cause hemolytic adverse reactions in patients with G6PD deficiency, and measurement of G6PD levels is recommended before starting therapy 1
Regular Follow-up
Regular follow-up with hematology is recommended, especially after hemolytic episodes, to monitor for any signs of hemolysis and to adjust management as needed.
Key Recommendations
- Screening for G6PD deficiency is recommended before starting therapy with an oxidant drug in patients with a predisposing racial or ethnic background 1
- Methylene blue should be used with caution in patients with G6PD deficiency 1
- Patient education is essential to prevent hemolytic crises 1
From the FDA Drug Label
WARNINGS Hemolytic anemia and G6PD deficiency Due to the risk of hemolytic anemia in patients with G6PD deficiency, G6PD testing has to be performed before using primaquine. In case of mild to moderate G6PD deficiency, a decision to prescribe primaquine must be based on an assessment of the risks and benefits of using primaquine If primaquine administration is considered, baseline hematocrit and hemoglobin must be checked before treatment and close hematological monitoring (e. g. at day 3 and 8) is required. Adequate medical support to manage hemolytic risk should be available.
The management approach for patients with G6PD deficiency includes:
- G6PD testing before using primaquine
- Assessment of risks and benefits of using primaquine in patients with mild to moderate G6PD deficiency
- Baseline hematocrit and hemoglobin checks before treatment
- Close hematological monitoring (e.g., at day 3 and 8)
- Availability of adequate medical support to manage hemolytic risk
- Consideration of alternative treatments if primaquine is contraindicated or not recommended 2
From the Research
Management Approach for Patients with G6PD Antibodies
The management approach for patients with Glucose-6-phosphate dehydrogenase (G6PD) antibodies involves careful consideration of medication use to avoid triggering hemolysis.
- Medications that should be avoided in individuals with G6PD deficiency include dapsone, methylthioninium chloride (methylene blue), nitrofurantoin, phenazopyridine, primaquine, rasburicase, and tolonium chloride (toluidine blue) 3.
- Other medications, such as ciprofloxacin, glibenclamide, ofloxacin, sulfamethoxazole/cotrimoxazole, sulfasalazine, hydroxychloroquine, glimepiride, mesalazine, and sulfacetamide, have been prescribed safely to G6PD-deficient patients in normal therapeutic dosages 4.
- It is essential to diagnose G6PD deficiency promptly and manage acute hemolytic anemia effectively 5.
- G6PD deficiency should be considered in patients who experience acute hemolysis after exposure to known oxidative medications, infection, or ingestion of fava beans 6.
- G6PD testing can be done to reconcile safety with cost, especially in populations where G6PD deficiency is common 7.
Medication Use in G6PD-Deficient Patients
Medication use in G6PD-deficient patients requires careful consideration to avoid triggering hemolysis.
- Certain medications, such as rasburicase, primaquine, dapsone, pegloticase, and methylene blue, should not be used until a G6PD diagnostic test has been performed 6.
- The use of medications that can trigger hemolysis in G6PD-deficient patients is a significant concern, and healthcare providers should be aware of the potential risks and take steps to mitigate them 3, 4, 5, 6, 7.