Glucose-6 Phosphate Dehydrogenase (G6PD), Quantitative Test
About Glucose-6 Phosphate Dehydrogenase (G6PD), Quantitative Test
| Field | Value |
|---|---|
| Also Known As | G6PD test, G6PD quantitative test, G6PD deficiency test, Glucose-6-phosphate dehydrogenase test, RBC G6PD test, G-6-PD |
| Sample Type | Venous blood (EDTA tube) |
| Fasting Required | No fasting required |
| Report Time | 1 to 3 business days |
| Recommended For | Males and females of all ages; particularly those with African, Mediterranean, Middle Eastern, or Asian ancestry |
| Price | Starting at ₹470 |
What Is a Glucose-6 Phosphate Dehydrogenase (G6PD), Quantitative Test?
The G6PD test measures the activity of an enzyme called glucose-6-phosphate dehydrogenase in your red blood cells. This enzyme helps protect red blood cells from damage caused by certain foods, medicines, and infections.
The G6PD quantitative test or G6PD deficiency test gives a precise numerical reading of enzyme activity, rather than a simple pass or fail result. A blood sample drawn from a vein in your arm is all that is needed.
What Does a Glucose-6 Phosphate Dehydrogenase (G6PD), Quantitative Test Measure?
The glucose-6-phosphate dehydrogenase test looks at two things in your blood sample. Here is a brief summary of each:
| Component | What It Tells Us |
|---|---|
| G6PD enzyme activity | How well the G6PD enzyme is working in your red blood cells, expressed in IU per gram of haemoglobin |
| Total haemoglobin concentration | The amount of haemoglobin (the protein that carries oxygen) in your blood, used to normalise the enzyme activity reading |
Together, these two measurements show whether your red blood cells have enough G6PD to protect themselves from oxidative stress, which means harmful chemical damage that can cause them to break down.
Why Is a Glucose-6 Phosphate Dehydrogenase (G6PD), Quantitative Test Done?
A doctor may order this test for several reasons, from investigating unexplained symptoms to confirming a suspected inherited condition.
Common Symptoms That May Require This Test
The following symptoms often lead a doctor to request a G6PD deficiency test:
- Unexplained fatigue or weakness
- Pale skin or pale appearance inside the eyelids
- Jaundice, meaning yellowing of the skin or eyes
- Dark or tea-coloured urine
- Shortness of breath
- Rapid heartbeat
- An enlarged spleen detected during a physical examination
Conditions This Test Can Help Detect
The RBC G6PD test can help identify several conditions, including:
- G6PD deficiency, an inherited disorder in which red blood cells break down prematurely
- Haemolytic anaemia, where red blood cells are destroyed faster than the body can produce new ones
- Neonatal hyperbilirubinaemia, which is high bilirubin (a yellow pigment) in newborns that can sometimes progress to kernicterus (brain damage from very high bilirubin)
- Chronic non-spherocytic haemolytic anaemia, a severe form in which red blood cell breakdown continues without an obvious external trigger
How to Prepare and What to Expect
The G6PD quantitative test requires very little preparation, but a few simple steps will help ensure an accurate result.
Do You Need to Fast?
No fasting is required for this test. You can eat and drink normally before your appointment. However, your doctor may advise you to temporarily avoid fava beans and certain medicines before the sample is collected.
Practical Tips Before Your Test
Keep the following points in mind before your appointment:
- Avoid fava beans (also called broad beans) if your doctor advises, as they can lower G6PD activity temporarily
- Tell your doctor about all medicines you are taking, particularly antimalarials, sulfa drugs, and aspirin, as these can affect results
- If you have recently had a blood transfusion or a haemolytic episode (a period when your red blood cells were breaking down), let your doctor know, as timing your test correctly is important for accuracy
- Wear a short-sleeved top or clothing with sleeves that roll up easily for the blood draw
Step-by-Step Procedure
Here is what you can expect during sample collection:
- A trained phlebotomist (the healthcare professional who collects blood samples) will ask you to sit comfortably and extend your arm.
- A small elastic band is placed around your upper arm to make the vein easier to locate.
- The skin over the vein is cleaned with an antiseptic wipe.
- A small needle is gently inserted. You may feel a brief, mild sting at this point.
- A small amount of blood is drawn into a collection tube. The whole process usually takes under five minutes.
- A small bandage is placed over the site, and your sample is labelled and sent to the laboratory for analysis.
Factors That Can Affect Accuracy
Several factors can influence the accuracy of your G6PD test result:
- A recent blood transfusion can mask deficiency, as the donor's red blood cells may carry normal G6PD activity
- Testing during or shortly after a haemolytic episode may produce a falsely normal or falsely elevated result because younger red blood cells carry higher G6PD activity
- A high white blood cell count can also affect the enzyme activity reading
- Iron deficiency anaemia may lead to a falsely high result when certain testing methods are used
Understanding Your Glucose-6 Phosphate Dehydrogenase (G6PD), Quantitative Test Results
Your results show how active the G6PD enzyme is in your red blood cells. A doctor will review the numbers alongside your symptoms and medical history before drawing any conclusions.
| Category | G6PD Activity Level | Unit |
|---|---|---|
| Normal (adults) | 5.5 to 20.5 | U/g Hb |
| Intermediate (females only) | 10-60% of normal median (moderate deficiency; heterozygotes) | U/g Hb |
| Deficient | <10% normal (severe deficiency) | U/g Hb |
These ranges are general guidelines and vary by lab method, age and population. Your doctor will interpret your results based on your age, health history, and other factors. Always consult a qualified healthcare professional for personalised medical advice.
A normal result in a man makes G6PD deficiency unlikely, and any anaemia present may have a different cause. A low result suggests deficiency, though the timing of the test matters greatly. High readings in adults usually reflect a large number of young red blood cells circulating in the bloodstream rather than a separate condition.
Results During Special Conditions
Certain situations can make results harder to interpret. Blood transfusions received within the four months before testing may cause results to appear normal even when deficiency is present. Testing during or shortly after a haemolytic episode is not recommended, as the G6PD level may appear falsely elevated. If deficiency is strongly suspected but the result is normal, retesting at least three months later is advisable.
How to Maintain Healthy Levels
People with confirmed G6PD deficiency can often stay well by following a few straightforward steps:
- Avoid known dietary triggers, particularly fava beans and products containing naphthalene, such as mothballs
- Always inform any doctor, dentist, or pharmacist about your G6PD status before starting a new medicine
- Stay up to date with vaccinations, as infections are a common trigger for haemolytic episodes
Glucose-6 Phosphate Dehydrogenase (G6PD), Quantitative Test Price and Home Collection
The G6PD test price starts at ₹470, and home collection is available so you can have your blood drawn from the comfort of your home. Approximate prices across major cities are listed below:
| City | Approximate Price (₹) |
|---|---|
| Mumbai | ₹470 |
| Kolkata | ₹470 |
| Bangalore | ₹470 |
| Hyderabad | ₹470 |
| Pune | ₹470 |
| Bhopal | ₹470 |
| Indore | ₹470 |
| Chennai | ₹470 |
Prices are indicative and may vary by location. Please confirm the current price at the time of booking.
How to Book
- Select the test on the Lupin Diagnostics website
- Choose your city and preferred time slot
- Opt for home sample collection by a certified phlebotomist, or visit your nearest Lupin Diagnostics centre
- Receive your report via email or WhatsApp within the stipulated turnaround time
Home Collection
Lupin Diagnostics offers home sample collection for the G6PD test across cities in India, so you do not need to travel to a lab. All samples are processed in NABL-accredited laboratories by experienced technologists. Your digital report is delivered securely via email or WhatsApp once ready.
Frequently Asked Questions
G6PD deficiency is an inherited condition in which the body produces too little of the G6PD enzyme or none at all. Without enough of this enzyme, red blood cells become fragile and can break down when exposed to certain foods, medicines, or infections. Most people with the condition live normally as long as they know their triggers and avoid them.
Anyone with symptoms of haemolytic anaemia, such as jaundice, dark urine, or unusual fatigue, may need this test. Newborns with prolonged jaundice lasting beyond two weeks are also commonly tested. If there is a family history of G6PD deficiency, a doctor may recommend testing even without symptoms.
Common triggers include fava beans, viral and bacterial infections, and certain medicines, such as antimalarials, sulfa antibiotics, and some pain relievers, including aspirin and ibuprofen. Knowing and avoiding these triggers is the most effective way to prevent episodes.
No fasting is needed before the G6PD quantitative test. You can eat and drink as normal. The main preparation involves avoiding certain medicines and foods if your doctor advises, and timing the test away from any recent haemolytic episode or blood transfusion.
The test is most accurate when performed at least a few weeks after a haemolytic episode and at least four months after a blood transfusion. If tested too soon after either event, the result may appear falsely normal. If your doctor still suspects deficiency despite a normal result, they may recommend repeating the G6PD test after three months.
There is no cure for G6PD deficiency. However, the condition does not affect life expectancy, and most people with it do not experience problems as long as they avoid known triggers. Management is focused on awareness and prevention rather than ongoing medication.
The condition is more common in people of African, Mediterranean, Middle Eastern, and Asian descent. It mainly affects men, as the gene involved is carried on the X chromosome. Women can carry the faulty gene and pass it on to their children, though they are less likely to experience severe symptoms themselves.
About G6PD Test
G6PD is the abbreviation of an enzyme, glucose-6-phosphate dehydrogenase, that helps in the proper functioning of red blood cells (RBCs). RBCs transport oxygen from the lungs to all the cells of the body for optimal health, growth, and reproduction.
This test measures the amount of glucose-6-phosphate dehydrogenase present in the blood. Its deficiency leads to a condition called G6PD deficiency, which is a genetic disorder mostly affecting males. A genetic mutation in the G6PD gene leads to the breakdown of RBCs. This condition, where the body destroys RBCs at a faster rate than it can replace them, is called hemolytic anemia. People with this deficiency show symptoms only when they are exposed to certain “triggers,” including broad beans, bacterial and viral infections, and anti-malaria medicines.
G6PD test is also known as
G6PD deficiency test, G-6-PD, RBC G6PD test, glucose-6-phosphate dehydrogenase test
Test preparation
No special preparation is required for this test. In this test, a fine needle is inserted into a vein in your arm to draw out a blood sample, which is collected in a test tube or vial. In the case of infants, blood is drawn from the heel of the baby.
Interpretation of results
Except for individuals with CNSHA, those with G6PD deficiency do not show any symptoms (asymptomatic) unless faced with a “trigger” such as broad beans, bacterial or viral infections, or anti-malaria drugs.
It’s these triggering factors that can lead to acute hemolytic anemia (AHA) in individuals with G6PD deficiency. If a G6PD genetic mutation is detected in a person, he is most likely to exhibit some of the symptoms associated with G6PD deficiency, to varying degrees. Thus, it is important to avoid triggers that can lead to hemolytic anemia.
Frequently Asked Questions
There are no such major precautions required to be taken before taking the test. A person about to take the G6PD test does not need to stop eating or drinking (fasting) before the test. However, certain foods such as broad beans and medications (sulfa drugs) such as antibacterial medicines, anti-malaria drugs, etc. should be avoided right before the test is taken. These are potential triggers for hemolytic anemia. Please inform your healthcare provider prior about the medicines or foods you take and follow their instructions closely.
Many people with G6PD deficiency do not show any symptoms of hemolytic anemia and can carry on with their normal activities without any hindrances. However, people prone to hemolytic anemia should always avoid “triggers.” In some cases, the symptoms of hemolytic anemia become severe and require immediate medical attention.
Women with slightly lower levels of G6PD may be “carriers” of G6DP deficiency. This means that they have one normal G6PD gene and one defective G6PD gene. Such females rarely show any symptoms as their normal G6PD gene is capable of producing enough RBCs. However, there is a possibility of passing on the defective gene to their offspring.
If you are on a medication that triggers mild or moderate G6PD deficiency, your healthcare provider might put you on a low dose of the “trigger” medication. In such cases, a complete blood count test is required as a monitoring test along with the G6PD test.
Triggers such as broad beans, bacterial and viral infections, and anti-malarial drugs can cause hemolytic anemia in an individual. Non-steroidal anti-inflammatory drugs (NSAIDs) should also be avoided by a person prone to an attack of hemolytic anemia.
Glucose-6 Phosphate Dehydrogenase (G6PD), Quantitative Test
