G6PD is an enzyme that helps protect red blood cells from being destroyed after they are exposed to certain "triggers" (certain medicines and some foods). When red blood cells are destroyed, the low blood cell counts cause a temporary condition known as "anemia" . Some people do not have enough G6PD to protect their red blood cells . This condition is known as G6PD deficiency. G6PD deficiency is caused by inherited variations in the G6PD gene. Because this is a genetic condition, G6PD deficiency is a life-long condition.
More than one hundred such variations (changes) can exist in the G6PD gene. These changes can lead the body to produce a G6PD enzyme with little or no function. There is a system to classify people into three categories based on how well their G6PD prevents red blood cell damage. Clinicians use that system to help guide drug therapy decisions.
G6PD deficiency
People with G6PD deficiency have little or no working G6PD enzyme. About 400 million people have deficient G6PD enzyme activity. This deficiency is more common in people of African, Mediterranean or Southeast Asian descent. About 2 percent of people fall into this group. Without enough G6PD, certain medicines and foods can cause red blood cells to break down and lose their ability to carry oxygen. This condition is known as "hemolytic anemia"
| Medicines that should to be avoided in people with G6PD deficiency include: | |
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| Medicines that should be used with caution in patients with G6PD deficiency include: | ||
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| Certain foods and chemicals should also be avoided. These include fava beans and products such as naphthalene (found in moth balls). To learn more about medicines that should be used with caution if you are G6PD deficient, talk to your doctor or pharmacist. | ||
Variable G6PD enzyme activity
Patients in this group may have G6PD activity ranging from normal to deficient. A G6PD enzyme activity test can be used to find out the G6PD activity of patients in this group. About 2 percent of people fall into this group.
Normal G6PD enzyme activity
Most medicines don't need to be adjusted for this group:
About 96 percent of people have normal G6PD enzyme function. No medicines or foods should be avoided based on G6PD status alone.
More information for patients
- "Do you know..." info sheet: G6PD deficiency
- "Do you know…" info sheet: G6PD deficiency (in Spanish)
More information for healthcare professionals
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