Inherited disorders: G6PD deficiency

Last updated: Monday, March 13, 2017

Glucose-6-phosphate dehydrogenase (G6PD) is an enzyme that safeguards red blood cells and protects them from damage. When there is an inherited G6PD deficiency, certain triggers can cause an acute illness because red blood cells become unstable and break down or haemolyse. This is called acute haemolytic anaemia, and some of the common triggers are summarised below:

The main food that can trigger an acute attack is broad beans. When a haemolytic episode occurs, then symptoms may include some or all of the following:

The duration of symptoms arising from an acute attack depend on its severity. However, the process of erythropoiesis, by which the body produces new red blood cells, is rapid and newly synthesised cells are unaffected once the trigger has gone away. People from certain parts of the world are more likely to suffer from G6PD deficiency, such as those who are of African, Middle Eastern or Mediterranean descent. It is also more common in men.

Medicines and G6PD deficiency 

The genetic make-up of the individual patient with G6PD deficiency affects whether a specific medicine causes an acute episode or not, and the severity of it. So while one sufferer may tolerate a particular medicine, another may react to it. However, the effect of medicines is usually dose-related as well: the risk of provoking haemolytic anaemia is greater with bigger doses, and bigger doses also cause more severe symptoms.

You can always check to see which medicines are regarded as unsafe by looking in the G6PD deficiency section of the BNF.