Glucose 6-phosphate, drug reaction

In some drug reactions, several of these hypersensitivity responses may present simultaneously. Some adverse reactions to drugs may be mistakenly classified as allergic or immune when they are actually genetic deficiency states or are idiosyncratic and not mediated by immune mechanisms (eg, hemolysis due to primaquine in glucose-6-phosphate dehydrogenase deficiency, or aplastic anemia caused by chloramphenicol). 

Favism is the haemolysis obseived after eating Vica fava. This reaction is observed in individuals with glucose-6-phosphate dehydrogenase deficiency. This common deficiency is also responsible for haemolysis in response to the antimalarial drug primaquine and others. 

It is becoming increasingly evident that a number of adverse reactions to drugs are due to genetically transmitted inborn enzyme abnormalities or deficiencies. The best known example of this category is the hereditary relative deficiency of the enzyme glucose-6-phosphate-dehydrogenase (G-6-PD), which occurs in 5% to 10% of Mediterranean littoral races, blacks, Pakistanis, and Sephardic Jews. This condition renders affected individuals susceptible to acute hemolytic ane-... 

G6PD deficiency (glucose 6-phosphate dehydrogenase enzyme deficiency) A genetically inherited condition, relatively common in Indian, African and some Meditteranean races. In affected people serious adverse reactions occur when they take certain drugs, e.g. the antimalarial drug primaquine, which causes red blood cell haemolysis leading to severe anaemia. 

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