From the FDA Drug Label
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 The FDA drug label does not answer the question.
From the Research
Yes, a patient can have Glucose-6-phosphate dehydrogenase (G6PD) deficiency without experiencing any symptoms. G6PD deficiency is an inherited enzyme disorder that affects approximately 400 million people worldwide, making it one of the most common enzyme deficiencies. Most individuals with G6PD deficiency remain asymptomatic throughout their lives unless they are exposed to specific triggers. These triggers include certain medications (such as antimalarials like primaquine, antibiotics like sulfamethoxazole, and analgesics like aspirin), infections, fava beans, and oxidative stress. When exposed to these triggers, affected individuals may develop hemolytic anemia, characterized by the rapid destruction of red blood cells, leading to symptoms like fatigue, jaundice, dark urine, and back or abdominal pain. The reason for this asymptomatic baseline state is that G6PD deficiency primarily affects red blood cells' ability to handle oxidative stress. Under normal conditions, the reduced enzyme activity is sufficient to maintain red blood cell integrity, but when oxidative challenges occur, the cells cannot produce enough NADPH to protect themselves, resulting in hemolysis. This is why patients with G6PD deficiency should be educated about trigger avoidance even if they've never experienced symptoms, as supported by the most recent study 1.
Some key points to consider in the management of G6PD deficiency include:
- Avoiding oxidative stressors, such as certain medications and fava beans
- Educating patients about the risks and signs of hemolytic anemia
- Monitoring for signs of hemolysis, especially after exposure to triggers
- Considering alternative treatments for conditions that may require medications known to trigger hemolysis in G6PD-deficient patients, as seen in the case report of a patient with G6PD deficiency and COVID-19 pneumonia 2
- The use of certain medications, such as trimethoprim-sulfamethoxazole, may be considered on a case-by-case basis, as some studies suggest that the benefits may outweigh the risks in certain populations 3.
Overall, the management of G6PD deficiency requires a comprehensive approach that takes into account the patient's individual needs and circumstances, with a focus on preventing hemolysis and managing symptoms if they occur. The most important consideration is to prioritize the patient's safety and well-being, and to take a cautious approach when it comes to exposure to potential triggers.