G6PD Test

Why this test may be ordered

• If you have symptoms of hemolytic anemia, such as fatigue, pale skin, jaundice, rapid heart rate, shortness of breath, or dark urine.
• If your newborn has jaundice that doesn't go away in two weeks and is not caused by another condition.
• If you have a family history of G6PD deficiency.

Preparation and collection

There are no special preparations needed for a G6PD test.

A health care professional will take a blood sample from a vein in your arm, using a small needle. This usually takes less than five minutes. If your baby is being tested, a health care provider will clean your baby's heel with alcohol and poke the heel with a small needle.

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.

Understanding results

If you don't have enough G6PD, it's known as G6PD deficiency. G6PD deficiency can cause the destruction of your red blood cells.

• Lower than normal amount of G6PD: If your results show you have lower than normal amounts of G6PD, it means you have a G6PD deficiency. Limitation: But your symptoms and risk of getting hemolytic anemia can vary, depending on your personal health history and exposure to triggers. Next step: Your provider can help you figure out which substances to avoid.
• Slightly lower than normal amount of G6PD (in women): If you are a woman with slightly lower than normal amounts of G6PD, you may be a carrier of a G6PD deficiency. That means you have one defective G6PD gene and one normal G6PD gene. Limitation: You might not have symptoms, since your normal G6PD genes usually make enough healthy red blood cells. But you have a risk of passing on the defective gene to your children. Next step: Your provider can help you figure out which substances to avoid.
• Normal amount of G6PD (in men): If you are a man with a normal amount of G6PD, you are unlikely to have a deficiency. Limitation: Your provider may want to repeat the G6PD test in a few weeks if you had the test during an episode of hemolytic anemia. Next step: If you have anemia, it may be due to another cause.

• Your symptoms and risk of getting hemolytic anemia can vary, depending on your personal health history and exposure to triggers.
• If you are a woman with slightly lower than normal G6PD, you may be a carrier and might not have symptoms, but you can still pass the defective gene to your children.
• If the test is performed during an episode of hemolytic anemia, the results may be affected and your provider may want to repeat the test in a few weeks.

What to do next

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

• What are the common triggers I should avoid if I have G6PD deficiency?
• If I am a carrier, what is the chance that my children will inherit G6PD deficiency?
• Should I avoid any specific medications or foods on a regular basis?

Evidence source

Source: U.S. National Library of Medicine (MedlinePlus). Practices and reference ranges may differ in your country.

U.S. National Library of Medicine: G6PD Test

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