What is G6PD deficiency?

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a lifelong genetic disorder. It causes your red blood cells to break down if you are exposed to certain triggers. People with G6PD deficiency are normally healthy but must avoid these triggers. It is a common inherited deficiency, especially within certain populations.

The breakdown of red blood cells, called 'haemolysis', can lead to anaemia (lack of red blood cells) and jaundice (the yellowing of skin and eyes).

If you have G6PD deficiency, certain triggers cause your red blood cells to be destroyed faster than they can be replaced. This is known as acute haemolytic anaemia (AHA), and can be life-threatening.

Triggers can include:

• medicines such as some antibiotics, some malaria medicines, aspirin, some anti-cancer medicines and large doses of vitamin C
• some chemicals, including the active ingredient in mothballs (naphthalene)
• some foods, particularly fava beans (broad beans), tonic water and blueberries
• infections, for example, some viral or bacterial infections

What are the symptoms of G6PD deficiency?

Most people with G6PD deficiency live without symptoms. If you are exposed to a trigger and go on to develop haemolytic anaemia, you may experience:

• dark-coloured urine (wee)
• yellow skin, eyes or tongue
• very pale skin
• a very fast heart rate and breathlessness
• low back pain
• fever
• diarrhoea, nausea and/or abdominal pain

Newborn babies with G6PD deficiency may develop jaundice, if they experience symptoms.

What causes G6PD deficiency?

People with G6PD deficiency do not have enough of the enzyme called glucose-6-phosphate dehydrogenase (G6PD). This enzyme helps protect your cells from damage from a chemical process called oxidative stress. If you do not have this enzyme, your red blood cells have no way to protect themselves from this damage.

G6PD deficiency is a lifelong genetic condition that is normally inherited through the female line. It is more common in males, and people with a Mediterranean, African, Asian, South American or Middle Eastern background.

When should I see my doctor?

You should see your doctor if your G6PD deficiency is triggered. This can lead to acute haemolytic anaemia, and needs medical attention.

See your doctor as soon as possible if you or your child has been diagnosed with G6PD deficiency and develops:

• jaundice (yellow skin and eyes)
• dark-coloured urine (wee)
• pale skin
• lethargy
• fever

How is G6PD deficiency diagnosed?

G6PD deficiency is diagnosed with a blood test. Your doctor might order this blood test if your baby has jaundice that does not go away.

If you have symptoms, blood tests can also rule out other causes of your symptoms. There is also a specific test that can check for the presence of the G6PD enzyme.

If a child in your family is diagnosed with G6PD deficiency or you have a family history of this condition, it's a good idea to have your other children tested.

How is G6PD deficiency treated?

Most people do not need any treatment — they can manage their G6PD deficiency by avoiding the triggers. Your doctor will give you a list of things to avoid and tips to manage the condition.

If you have a diagnosis of G6PD deficiency, tell all your doctors so they don't prescribe a medicine that could trigger the condition.

If you develop anaemia, it will need to be treated. This sometimes involves a blood transfusion.

Babies with jaundice are usually treated with phototherapy (light therapy). This involves being placed under special lights. In severe cases, a treatment known as 'exchange transfusion' may be needed. This involves removing some of your baby's blood and replacing it with donor blood or plasma.

Having a virus or other infection can stress the body and lead to haemolysis in people with G6PD deficiency. See your doctor if you or your child has G6PD deficiency and develops an infection.

What are the complications of G6PD deficiency?

The main complication of G6PD deficiency is acute haemolytic anaemia, which occurs after exposure to a trigger.

A common form of acute haemolytic anaemia is known as favism, which develops if a person with G6PD deficiency eats fava beans (also called broad beans). After eating fava beans, acute haemolytic anaemia can develop quickly. Symptoms of favism include the symptoms of haemolytic anaemia.

People with favism always have G6PD deficiency, but not all people with G6PD deficiency react this strongly to fava beans. Children are more likely to experience favism.

If you are breastfeeding and your child has G6PD deficiency, avoid eating fava beans. This can trigger symptoms in your baby.

Can G6PD deficiency be prevented?

G6PD deficiency can't be prevented. It is a genetic condition that you are born with. Episodes of acute haemolytic anaemia can be prevented by avoiding known triggers.

Before you buy medicine without a prescription, talk to your pharmacist. Tell them you have G6PD deficiency and ask them for advice.

Looking for a medicine? To search by brand name or active ingredient, use the Medicines information search feature.

You should also be careful about using any herbal and alternative medicines, as some of these may also trigger acute haemolytic anaemia.

Since G6PD deficiency can be triggered by infections, making sure that you are up to date with your vaccinations can reduce your chance of acute haemolytic anaemia.

Resources and support

• The Royal Children's Hospital Melbourne has a fact sheet with more information about G6PD deficiency.
• The Western Sydney Local Health District has more information about G6PD deficiency.
• Visit the G6PD Deficiency Favism Association for more information on living with G6PD deficiency.
• Read more about G6PD deficiency prevention and vaccines at the Melbourne Vaccine Education Centre.

You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with you 24 hours a day, 7 days a week.