Nitrofurantoin: Dose adjustment for renal impairment

  • Dosing recommendations are based on estimated glomerular filtration rate (eGFR) .
  • Dose adjustment may not be appropriate in ACUTE renal impairment secondary to SEPSIS. In this case it is important to treat the infection aggressively for the first 24hrs and re-check renal function before reducing the dose accordingly.
  • (In 'acute on chronic' renal impairment the initial dose should correspond to the previous level of chronic renal impairment).


Nitrofurantoin is contraindicated in patients with an estimated glomerular filtration rate (eGFR) of less than 45 ml/min.



eGFR (ml/min) Dose
Greater than 45

Dose as in normal renal function

Less than 45

Contraindicated *


*A short course (3 to 7 days) may be used with caution in certain patients with an eGFR of 30 to 44 ml/min. Only prescribe when the benefits of nitrofurantoin are considered to outweigh the risks of side effects. Toxic plasma concentrations can occur causing adverse effects, e.g. neuropathy, blood dyscrasias.

Refer to Renal Pharmacist or Medicines Information for advice on dosing in haemodialysis and peritoneal dialysis.