G6PD Test: MedlinePlus Medical Test (2024)

What is a G6PD test?

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:

Fava beans, also called broad beans
Viral infections
Bacterial infections
Certain antibiotics
Anti-malaria medicines
Other medicines, including nonsteroidal, anti-inflammatory drugs (NSAIDs) such as ibuprofen and aspirin

Other names: G6PD deficiency test, glucose-6-phosphate dehydrogenase test

What is it used for?

A G6PD test is used to check for a G6PD deficiency (not enough G6PD).

Why do I need a G6PD test?

You may need a G6PD test if you have symptoms of hemolytic anemia. These include:

Fatigue
Pale skin or jaundice, a condition that causes your skin and eyes to turn yellow
Rapid heart rate
Shortness of breath
Dark or yellow-orange colored urine

Your newborn baby might need a G6PD test if he or she has jaundice that doesn't go away in two weeks and/or is not explained by another condition. Your baby may also be tested if you have a family history of G6PD deficiency.

What happens during a G6PD test?

A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.

Will I need to do anything to prepare for this test?

There are no special preparations needed for a G6PD test.

Are there any risks to this test?

There is very little risk to having a blood test. You may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.

Your baby may feel a little pinch when the heel is poked, and a small bruise may form at the site. This should go away quickly.

What do the results mean?

If your results show you have lower than normal amounts of G6PD, it means you have a G6PD deficiency. But your symptoms and risk of getting hemolytic anemia can vary depending on your personal health history and exposure to triggers.

Women who have slightly lower than normal amounts of G6PD may be "carriers" of a G6PD deficiency. That means they have one defective G6PD gene and one normal G6PD gene. These women rarely have symptoms, as their normal G6PD genes usually make enough healthy red blood cells. But they have a risk of passing on the defective gene to their children. Male children are more likely to develop G6PD symptoms than female children.

Learn more about laboratory tests, references ranges, understanding results.

Is there anything else I need to know about a G6PD test?

Most people with G6PD deficiency can manage their condition and prevent symptoms by avoiding triggering substances. Your health care provider can help you figure out which substances to avoid.

References

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G6PD Deficiency: Favism [Internet]. www.g6pd.org; What is G6PD Deficiency (English); [cited 2021 Apr 23]; [about 3 screens]; Available from: https://www.g6pd.org/en/G6PDDeficiency/WhatIsIt.aspx
Kids Health from Nemours [Internet]. Jacksonville (FL): The Nemours Foundation; c1995–2021. What is G6PD Deficiency?; [cited 2021 Apr 23]; [about 3 screens]. Available from: https://kidshealth.org/en/parents/g6pd.html
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March of Dimes [Internet]. Arlington (VA): March of Dimes; c2021. Newborn Jaundice; [cited 2021 Apr 23]; [about 3 screens]. Available from: https://www.marchofdimes.org/complications/newborn-jaundice.aspx
National Heart, Lung, and Blood Institute [Internet]. Bethesda (MD): U.S. Department of Health and Human Services; Blood Tests; [cited 2021 Apr 23]; [about 3 screens]. Available from: https://www.nhlbi.nih.gov/health-topics/blood-tests
NORD: National Organization for Rare Disorders [Internet]. Danbury (CT): NORD: National Organization for Rare Disorders; c2021. Glucose-6-Phosphate Dehydrogenase Deficiency; [cited 2021 Apr 23]; [about 3 screens]. Available from: https://rarediseases.org/rare-diseases/glucose-6-phosphate-dehydrogenase-deficiency/
UF Health: University of Florida Health [Internet]. Gainesville (FL): University of Florida Health; c2021. Glucose-6-phosphate dehydrogenase test; [updated 2021 Apr 23; cited 2021 Apr 23]; [about 2 screens]. Available from: https://ufhealth.org/glucose-6-phosphate-dehydrogenase-test
University of Iowa Stead Family Children's Hospital [Internet]. Iowa City (IA): The University of Iowa; c2021. Obtaining blood via heel stick; [cited 2021 Apr 23]; [about 2 screens]. Available from: https://uichildrens.org/health-library/obtaining-blood-heel-stick
University of Rochester Medical Center [Internet]. Rochester (NY): University of Rochester Medical Center; c2021. Health Encyclopedia: Glucose-6-Phosphate Dehydrogenase; [cited 2021 Apr 23]; [about 2 screens]. Available from: https://www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=167&contentid=g6pd
Very Well Health [Internet]. New York: About, Inc.; c2021. An Overview of G6PD Deficiency; 2020 Aug 23 [cited 2021 Apr 23]; [about 3 screens]. Available from: https://www.verywellhealth.com/g6pd-deficiency-401301