Question - The development of megaloblastic anemia has been attributed to both congenital and acquired problems. What is the general mechanism for the development of drug-induced (acquired) megaloblastic anemia?
Answer- The cited article notes “Drugs cause megaloblastic anemia by impairing the cellular availability or use of folic acid or vitamin B12. This may occur because of interference with the absorption, plasma transport, or delivery of folate or vitamin B12, competition for reducing enzymes, end-product inhibition of cofactor-mediated reactions, or physical destruction of the vitamins.” (Hesdorffer CS and Longo DL. Drug-induced megaloblastic anemia. 2015 NEJM 373:1649-1658)