Metformin hemolytic anemia

Meir A, Kleinman Y, Rund D, Da as N. Metformin-induced hemolytic anemia in a patient with glucose-6-phosphate dehydrogenase deficiency. Diabetes Care 2003 26(3) 956-7. 

Megaloblastic anemia is rare with metformin, but vitamin Bi2 concentrations can be reduced by metformin and phenformin (61) because of reduced absorption, and pre-existing deficiency can be exacerbated (41). Metformin can occasionally cause a hemolytic anemia. 

Hematologic Metformin-induced hemolytic anemia is rare and generally not fatal the time to onset of symptoms after starting metformin is about 10 days. A fatal case has been reported [41 ]. 

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