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 are available: 1) a microcrystalline form (Furadantin), 2) a macrocrystalline form (Macrodantin), and 3) a sustained release macrocrystalline form used twice daily (Macrobid). 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.

STORAGE: All formulations should be kept at room temperature, 15-30 C (59-86 F).

PRESCRIBED FOR: Nitrofurantoin is used to treat or prevent urinary tract infections.

DOSING: The recommended adult dose for treating urinary tract infections is 50-100 mg 4 times daily (Macrodantin, Furadantin) or 100 mg every 12 hours (Macrobid). Nitrofurantoin can be taken with or without meals. Taking it with meals increases its absorption into the body. The suspension can be mixed with water, milk, juice, or infant formula. It also is used once a day (or in some children, twice daily) to prevent urinary tract infections. It should not be used in persons with poor kidney function.

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