HomeLab TestsG6PD Test
Back to Lab Tests
G6PD Test
Reviewed by Medicinsk Expert•Last updated: 2026-10-22•Lab Tests

G6PD Test

The G6PD test measures an enzyme in your blood that protects red blood cells, helping to diagnose a genetic deficiency that can lead to hemolytic anemia.

Overview

G6PD (glucose-6-phosphate dehydrogenase) is an enzyme that helps red blood cells function properly. G6PD deficiency is an inherited genetic disorder that primarily affects men. It is more common in people of African, Mediterranean, or Asian descent.

When individuals with this deficiency are exposed to certain triggers, their red blood cells may be destroyed faster than the body can replace them, leading to hemolytic anemia. Common triggers include:

  • Fava beans (favism)
  • Viral or bacterial infections
  • Certain antibiotics and anti-malaria medicines
  • Nonsteroidal anti-inflammatory drugs (NSAIDs) like aspirin and ibuprofen

Why do I need a G6PD test?

You may need this test if you exhibit symptoms of hemolytic anemia, such as:

  • Fatigue
  • Pale skin or jaundice (yellowing of skin and eyes)
  • Rapid heart rate
  • Shortness of breath
  • Dark or yellow-orange urine

Newborns may be tested if they have persistent jaundice or a family history of the deficiency.

What happens during the test?

A healthcare professional collects a blood sample from a vein in the arm. For newborns, a small amount of blood is typically collected via a heel prick.

What do the results mean?

  • Lower than normal G6PD: Indicates a G6PD deficiency. The severity of symptoms depends on your health history and exposure to triggers.
  • Women with slightly lower levels: May be carriers of the defective gene. While they may not have symptoms, they can pass the gene to their children.
  • Normal levels: Suggest you are unlikely to have the deficiency. If anemia is present, it may be due to another cause.

Management

Most people with G6PD deficiency manage the condition by avoiding known triggers. Consult your healthcare provider to identify specific substances you should avoid.

Frequently Asked Questions

The genetic deficiency itself is present from birth and does not worsen with age. However, the severity of symptoms can vary throughout life depending on exposure to triggers. Some individuals may never experience significant symptoms if they avoid triggers, while others may have frequent episodes. It is important to note that the condition is lifelong, and there is currently no cure, only management through avoidance of known triggers.
No special preparation is typically required for a standard G6PD enzyme assay. You can eat and drink normally before the test. However, it is crucial to inform your healthcare provider if you have recently taken any medications, supplements, or consumed fava beans, as these can trigger a hemolytic episode and potentially affect the accuracy of the enzyme level measurement. If you are currently experiencing symptoms of anemia, your doctor may order additional tests to assess the extent of red blood cell destruction.
Yes, false negatives can occur, particularly if the test is performed during an active episode of hemolytic anemia. During a hemolytic crisis, the older, more enzyme-deficient red blood cells are destroyed, leaving behind newer red blood cells that may have higher levels of G6PD activity. This can temporarily mask the deficiency. If clinical suspicion remains high despite a normal result, your provider may recommend repeating the test after the acute episode has resolved or using alternative diagnostic methods.
G6PD deficiency is an X-linked recessive disorder, meaning it primarily affects males. Female carriers usually have enough enzyme activity to prevent symptoms but can pass the gene to their children. Newborns with the deficiency are at higher risk for severe jaundice (yellowing of the skin and eyes) because their immature livers struggle to process bilirubin, a byproduct of red blood cell breakdown. Early testing and monitoring of bilirubin levels are critical to prevent complications such as kernicterus, a type of brain damage caused by high bilirubin levels.
Source: MedlinePlus, National Library of Medicine

MedlinePlus brings together authoritative health information from the National Library of Medicine (NLM), the National Institutes of Health (NIH), and other government agencies and health-related organizations.

kontakt@hittavard.se

Ⓒ 2024. Alla rättigheter förbehålls av juxt ab

Sök
Om ossVillkor och policyVanliga frågorKontakta oss