Macrodantin (Nitrofuratoin)

  • Macrodantin is a bactericidal oral antibiotic
  • Used for: uncomplicated UTI’s, except those caused by Proteus, P. aeruginosa or Serratia
  • It cannot be used to treat pyelonephritis or systemic infections due to its poor serum levels
  • UTI prophylaxis should be avoided long term because of the potential to cause chronic pulmonary syndrome which can be fatal
  • Not recommended for patients with poor renal function
  • Side effects: Brown urine, anemia, neuropathy, pulmonary fibrosis, nausea & more
  • Pregnant women in their last week of pregnancy with a UTI should not be treated with Macrodantin
  • Can take with food to decrease nausea


Contraindications & Precautions 

  • Hypersensitivity  to drug class
  • History of hepatic impairment 
  • History of cholestatic jaundice 
  •  <1 mo of age
  • CrCl <60
  • Oliguria
  • Anuria
  • Pregnancy 38-42 wk gestation
  • Labor and delivery
  • Use with caution in patients with peripheral neuropathyanemia, DM, electrolyte abnormalitiesG6PD deficiency & recent antibiotic associated colitis hx


See CDC Treatment Recommendations


Adult Dosing 
Dosage forms: 25,50,100

Adult Dosing for UTI 

  • 50-100 mg PO Q 6 HR x7 days
  • CrCl <60: contraindicated

Adult Dosing for UTI prophylaxis

  • 50-100 mg PO Q HS
  • CrCl <60: contraindicated


Pediatric Dosing 
Dosage forms: 25,50,100

Pediatric Dosing for UTI 
1 mo and older

  • Dose: 5-7 mg/kg/day PO divided Q 6 HR x7 days; Max: 400 mg/day


Pediatric Dosing for UTI prophylaxis
1 mo and older

  • Dose: 1-2 mg/kg/day PO divided Q12-24 HR; Max: 100 mg/day
  • CrCl <60: contraindicated


***This is a study guide only & not intended for drug dosing 



Edmunds, M. W., & Mayhew, M. S. (2014). Pharmacology for the primary care provider (4th ed.). St. Louis, MO: Elsevier Mosby.

Harvey, R. A., Clark, M. A., Finkel, R., Rey, J. A., & Whalen, K. (2012). Pharmacology (5th ed.). Baltimore, MD: Lippincott.