Nitrofurantoin

C difficile risk
Low
Oral Bioavailability
Excellent

Dosing

For lower urinary tract infections onlyCystitis: Macrobid 100 mg PO BID

Contraindicated in infants < 1 month of age

0 - 40 eGFR40+ eGFRContraindicatedNitrofurantoin long acting 100 mg PO BID

General Information

Uncomplicated cystitis with eGFR > 40 ml/min

Pregnancy: Does not appear to be associated with congenital malformations with first trimester exposure. Recommended to avoid at time of delivery as there is a small increased risk of hemolytic anemia of the newborn.

Breastfeeding: Nitrofurantoin is transferred into breastmilk in very low amounts. Nitrofurantoin therapy is contraindicated when given directly to infants < 1 month of age due to the risk of hemolysis. Theoretically, this risk may also be present for infants exposed to nitrofurantoin via breastmilk however, no reports of hemolytic anemia in a breastfeeding neonate exposed to nitrofurantoin have been located. Caution, particularly in preterm infants and infants < 8 days old. An alternative antibiotic should be considered if possible. Breastfeeding should be avoided in infants with G6PD deficiency. Monitor the infant for signs of jaundice and GI intolerances.

  • Interstitial pneumonitis and fibrosis especially with prolonged use

  • Peripheral neuropathy

  • GI intolerance

  • Increased liver enzmes

  • Anemia

Cannot be used for the treatment of pyelonephritis.

Antimicrobial class: Reduced by bacterial flavoproteins to reactive intermediates that inactivate or alter bacterial ribosomal proteins leading to inhibition of protein synthesis, aerobic energy metabolism, DNA, RNA, and cell wall synthesis. Nitrofurantoin is bactericidal in urine at therapeutic doses.