This test measures the amount of G6PD in the blood. G6PD stands for glucose-6-phosphate dehydrogenase, an enzyme that helps red blood cells work properly. Red blood cells move oxygen from your lungs to every cell in your body. Your cells need oxygen to grow, reproduce, and stay healthy.

If you don’t have enough G6PD, it’s known as G6PD deficiency. This is a genetic disorder that mostly affects males. G6PD deficiency can cause the destruction of red blood cells. When red blood cells are destroyed faster than the body can replace them, it’s called hemolytic anemia. If you have hemolytic anemia, your cells don’t get all the oxygen they need.

Most people with G6PD deficiency don’t have symptoms of disease until they are exposed to certain “triggers,” which set off the destruction of red blood cells. Triggers include: