What is G6PD deficiency?
Glucose-6-phosphate dehydrogenase (G6PD) is a protein in a person’s red blood cells that helps the red blood cells function properly. Some people have less than the usual amount of G6PD in their red blood cells. This is called G6PD deficiency. In G6PD deficiency, a person’s red blood cells are prone to breaking down. This process is called hemolysis.
Most people with G6PD deficiency have completely normal health, and hemolysis does not happen all the time, but sometimes it can cause problems. Certain medications, foods, and stress (such as fevers or infections) can trigger hemolysis in people with G6PD deficiency. When hemolysis occurs, children can develop symptoms of anemia and jaundice. G6PD deficiency is a life-long condition.
G6PD deficiency is passed on from parents to children
G6PD deficiency is an inherited disorder, which means it is passed from one or both parents to their child. It typically affects males more than females.
About 400 million to 500 million people worldwide have G6PD deficiency. Anyone can have G6PD deficiency, but it is most common in people whose families come from Africa, the Mediterranean, the Caribbean and South-East Asia. The severity of G6PD deficiency varies based on the gene that a person has inherited.
Your child should not take certain medications
If your child has G6PD deficiency, they should not take any of the following medications:
- acetylsalicylic acid (ASA)
- ascorbic acid (Vitamin C)
- bupivacaine
- chloroquine
- ciprofloxacin
- dapsone
- hydroxychloroquine
- levofloxacin
- mefloquine
- methylene blue
- moxifloxacin
- nitrofurantoin
- nitroglycerin
- primaquine
- probenecid
- sulfamethoxazole-trimethoprim (Septra)
- sulfasalazine
This list contains the names of medications which have a high risk of causing haemolysis in patients with G6PD deficiency. This list may change over time. Sometimes medications that are not on this list can also cause problems. Tell your child’s health-care providers (including pharmacists) that they have G6PD deficiency and ask them to check before giving your child any medications, including herbal remedies. In some cases, a medication that is required for treatment is still prescribed despite a risk of hemolysis and your child has blood tests to monitor for hemolysis.
The risk and severity of hemolysis is almost always dose related. This means that if your child takes a higher dose of one of these medications, they are more likely to develop hemolysis, and it is more likely to be severe.
Your child should avoid mothballs, dyes and certain foods
Your child should not come in close contact with mothballs (naphthalene). Naphthalene may also be found in public toilet/urinal deodorizers. Some chemicals used in hair dyes and tattoos (black and red Egyptian henna) can cause hemolysis. Your child should avoid contact with chemicals used in hair dyes, henna and tattoos.
Your child should not eat fava beans. Some people with G6PD deficiency may need to avoid red wine, all beans, blueberries, soya products, tonic water and camphor.
G6PD deficiency can cause problems
Problems for newborn babies
Some babies develop jaundice (skin and whites of the eyes turn yellow) shortly after they are born. Severe jaundice can be serious for newborn babies if it goes untreated. It is usually treated by putting the baby under a special light for a few days.
Many babies with G6PD deficiency are diagnosed because they have jaundice soon after birth. Once the jaundice has passed, they should not get other problems from G6PD deficiency, as long as they avoid fava beans, mothballs and the medications listed above.
Problems for children and adults
Some children and adults with G6PD deficiency may develop haemolysis and anemia after they are exposed to any of the triggers listed below:
- fever or an infection
- the medications listed above
- eating fava beans
- contact with naphthalene or henna dyes
If your child is exposed to a trigger that causes hemolysis, sometimes there are no symptoms at all. In more serious cases, your child may have one or more of the following symptoms of anemia:
- pale skin
- fatigue
- rapid heartbeat
- rapid breathing
- shortness of breath
- jaundice
- backache
- belly pain
- headache
- dark, tea-coloured urine
If your child is experiencing any of these symptoms, call their health-care provider or go to the nearest Emergency Department. Once the trigger is removed or resolved, the symptoms of G6PD deficiency improve.