Nitrofurantoin is an antibiotic drug. It is only useful in the treatment of cystitis.
At the concentrations achieved in urine, nitrofurantoin is bacteriocidal. The mechanism of action of nitrofurantoin is unique and complex. The drug works by damaging bacterial DNA, since its reduced form is highly reactive. This is made possible by the rapid reduction of nitrofurantoin inside the bacterial cell by flavoproteins (nitrofuran reductase) to multiple reactive intermediates that attack ribosomal proteins, DNA respiration, pyruvate metabolism and other macromolecules within the cell. It is not known which of the actions of nitrofurantoin is primarily responsible for its bacteriocidal acitivity.
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Macrobid - Nitrofurantoin monohydrate. Product information for US residents in PDF format. [Acrobat Reader required]
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