nitrofurantoin, Macrodantin, Furadantin, Macrobid (cont.)

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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.

DRUG INTERACTIONS: High doses of probenecid (Benemid) or sulfinpyrazone (Anturane) can partially block the kidneys' elimination of nitrofurantoin. This can increase the blood concentrations of nitrofurantoin and the risk of toxicity from nitrofurantoin.

Concomitant administration of a magnesium trisilicate antacid may decrease the absorption of nitrofurantoin, reducing the effectiveness of nitrofurantoin.

NItrofurantoin may reduce the activity of live tuberculosis vaccine (BCG vaccine) and live typhoid vaccine. In laboratory tests, nitrofurantoin reduced the effect of quinolone antibiotics, for example, norfloxacin (Noroxin). Therefore, nitrofurantoin should not be combined with quinolone antibiotics.

PREGNANCY: Although there are no adequate studies of nitrofurantoin in pregnant women, many women have safely used it during pregnancy. However, nitrofurantoin should not be used near the time of delivery (38-42 weeks gestation) since it interferes with the immature enzyme systems in the red blood cells of newborns, damaging the cells and resulting in anemia.

NURSING MOTHERS: Nitrofurantoin is distributed into breast milk and should be used with caution in women who are breastfeeding.

SIDE EFFECTS: Common side effects include headache, rash, itching, nausea, vomiting, loss of appetite, diarrhea, and abdominal pain. The macrocrystalline form (Macrodantin) appears to cause less stomach upset. Stomach upset also can be minimized by using a lower dose or by taking nitrofurantoin with food or milk.

Medically Reviewed by a Doctor on 10/24/2014


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