Patient education: Glucose-6-phosphate dehydrogenase deficiency (The Basics)

What is glucose-6-phosphate dehydrogenase deficiency? — Glucose-6-phosphate dehydrogenase deficiency, or "G6PD deficiency," is a condition that involves the red blood cells. G6PD is a protein in red blood cells that protects them from being damaged. People with G6PD deficiency have too little G6PD in their red blood cells.

In people with G6PD deficiency, being exposed to certain foods, medicines, and chemicals can damage the red blood cells. This is called "hemolysis." If the body cannot make more red blood cells fast enough, it can lead to a condition called anemia.

G6PD deficiency is a condition people are born with. It is caused by a change in the G6PD gene. Males are more likely to have G6PD deficiency. G6PD deficiency is common in people whose ancestors came from Africa, the Mediterranean area, or parts of Asia, South America, or the Middle East. But it can affect anyone.

In most people with G6PD deficiency, hemolysis doesn't happen all of the time. Episodes of hemolysis happen only when they are triggered by something. Common triggers include:

●Certain infections

●Certain medicines, such as "sulfa" antibiotics and medicines to treat malaria

●Specific foods, such as fava beans

●Some chemicals used in hair dyes or tattoos

What are the symptoms of G6PD deficiency? — Symptoms depend on the person.

Most people have no symptoms until an episode of hemolysis is triggered by one of the things listed above. Then, symptoms can include:

●Jaundice, which is when the skin or the whites of the eyes turn yellow

●Pale skin, or paleness of the lips, tongue, or inside of the eyelid

●Dark-colored urine

●Back or belly pain

●Tiredness, fatigue, or headache caused by anemia

Sometimes, newborn babies can have jaundice (yellowing of the skin or white part of the eyes). In some cases, this can affect the brain.

Some people always have hemolysis, no matter what they eat or what medicines they take.

Is there a test for G6PD deficiency? — Yes. To check, your doctor or nurse will order different blood tests to check for anemia, hemolysis, and your G6PD level.

How is G6PD deficiency treated? — Treatment depends on your symptoms and how severe your anemia is. Most people just need to know which foods, medicines, and chemicals to avoid. Lists of medicines to avoid can be found on websites such as www.g6pd.org or from your doctor or nurse. Fava beans (and foods made from fava beans) trigger hemolysis in many people. But other kinds of beans are safe.

If you have symptoms caused by a medicine you take or a food you eat, your doctor or nurse will have you stop taking that medicine or eating that food. In general, avoid foods, medicines, and chemicals that commonly trigger symptoms.

People with severe anemia might be treated with a blood transfusion, but this is rare. This involves getting blood that has been donated by someone else. The donated blood goes into your vein through a thin tube called an "IV." This is very rarely needed. People with severe hemolysis might also need to get fluids through a vein.

Babies with jaundice are often treated with "light therapy," also called "bili lights." During light therapy, a doctor or nurse puts a baby under a special blue light (figure 1) or wraps a "light blanket" around the baby. This helps the baby's system get rid of the harmful parts of the destroyed red blood cells.

People with long-term anemia might be treated with a vitamin called folic acid (also called folate).

What if I want to get pregnant? — People with G6PD deficiency generally can have a normal pregnancy. If you want to get pregnant, talk to your doctor or nurse before you start trying. There might be special things you should do. You might also need to avoid certain medicines.

Also, there is a chance you will pass the gene for G6PD deficiency to your baby. If you have questions about this, you can talk with a genetic counselor or another person who specializes in genetic conditions.

More on this topic

Patient education: Complete blood count (CBC) (The Basics)
Patient education: Jaundice in babies (The Basics)

Patient education: Jaundice in newborn infants (Beyond the Basics)