Nitrofurantoin

C difficile risk
Low
Oral Bioavailability
Excellent
Cost
$1-2/day

Dosing

CrCl <30Contraindicated

Cystitis
Macrobid 100mg PO BID

General Information

Only for urinary tract infections. Not for use in pyelonephritis or prostatitis due to lack of penetration.

Interstitial pneumonitis and fibrosis especially with prolonged use.

Peripheral neuropathy.

Contraindicated for CrCl < 30 due to lack of urinary penetration at low CrCl

Two formulations exist for UTI treatment:

  • Nitrofurantoin monohydrate/macrocrystal - Macrobid - BID dosing (Formulary)

  • Nitrofurantoin macrocrystal - Macrodantin - QID dosing

BEERS list - nitrofurantoin prophylaxis is not recommended in elderly patients

Antimicrobial class: Nitrofuran

Pregnancy category: Nitrofurantoin may be used to treat infections during pregnancy:

  • Use during the first trimester should be limited to situations where no alternative therapies are available as evidence for association with birth defects is mixed.

  • Use during the second and third trimester (except as below) as a first line agent is appropriate

  • Contraindicated in pregnant patients at term (38 to 42 weeks' gestation), during labor and delivery, or when the onset of labor is imminent due to the possibility of hemolytic anemia in the neonate

  • Alternative antibiotics should be used in pregnant patients with G-6-PD deficiency

See ACOG 717 2017

Average serum half life: 1 hour

Biliary penetration: None

CSF penetration: None

Lung penetration: None

Urine penetration: Therapeutic