nitrofurantoin, Macrodantin, Furadantin, Macrobid

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GENERIC NAME: nitrofurantoin

BRAND NAMES: Macrodantin, Furadantin, Macrobid

DRUG CLASS AND MECHANISM: Nitrofurantoin is an antibiotic that is used for treating urinary tract infections caused by several types of bacteria. It is effective against E. Coli, Enterobacter cystitis, Enterococcus, Klebsiella, and Staphylococcus aureus. Nitrofurantoin interferes with the production of bacterial proteins, DNA, and cell walls. Bacteria cannot survive without a cell wall or multiply without DNA.

Three forms of nitrofurnatoin are available:

  • Furadantin, a microcrystalline form,
  • Macrodantin, a macrocrystalline, and
  • Macrobid, a sustained release form of macrocrystalline used twice daily.

The macrocrystalline form is more slowly absorbed than the microcrystalline form and is useful for patients who cannot tolerate the microcrystalline form. The FDA approved nitrofurantoin in 1953.



PREPARATIONS: Capsules: 25, 50, 75, and 100 mg. Oral suspension: 25 mg/5 ml.

Medically Reviewed by a Doctor on 10/24/2014

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