Nitrofurantoin

Renal impairment

• Check renal function before starting nitrofurantoin, especially in the elderly.
• The antibacterial efficacy of nitrofurantoin depends on adequate renal secretion into the urinary tract. Therefore, there is reduced efficacy of nitrofurantoin in renal impairment.
• Avoid if eGFR less than 45mL/min/1.73m².
  • A short course (3-7 days) may be used with caution in patients with an eGFR between 30-44mL/min/1.73m² to treat resistant pathogens, when the benefits of nitrofurantoin may outweigh the risks.
  • For more information see MHRA Drug Safety Update (February 2015) Nitrofurantoin now contraindicated in most patients with an estimated glomerular filtration rate (eGFR) of less than 45 ml/min/1.73m2[LD1] 
• HD/HDF/High Flux/PD: Contra-indicated.

Hepatic impairment

Use with caution. No dose adjustment required.

• Hepatic reactions including cholestatic jaundice, autoimmune hepatitis and chronic active hepatitis and hepatic necrosis have been reported with the use of nitrofurantoin.

• Be vigilant for symptoms and signs of liver dysfunction in patients taking nitrofurantoin for any duration, but particularly with long-term use, and monitor patients periodically for signs of hepatitis and for changes in biochemical tests that would indicate hepatitis or liver injury.
• For more information see MHRA Drug Safety Update (April 2023) Nitrofurantoin: reminder of the risks of pulmonary and hepatic adverse drug reactions

MHRA Drug Safety Update (February 2015):

Nitrofurantoin now contraindicated in most patients with an estimated glomerular filtration rate (eGFR) of less than 45 ml/min/1.73m2

MHRA Drug Safety Update (April 2023):

Nitrofurantoin: reminder of the risks of pulmonary and hepatic adverse drug reactions

• ADVANZ Pharma. Nitrofurantoin 50mg Capsules summary of product characteristics. Electronic Medicines Compendium. Last revision of the text 08/25 Available from: https://www.medicines.org.uk Accessed 23/3/26.
• The Renal Drug Database. Nitrofurantoin. Last updated 21/11/24 Available from: https://www.renaldrugdatabase.com Accessed 23/3/26
• British National Formulary. Nitrofurantoin. BNF online accessed via www.medicinescomplete.com Accessed 23/3/26.
• Sanford guide [online]. Nitrofurantoin. Last updated 13/3/26. Accessed via https://webedition.sanfordguide.com Accessed 23/3/26
• MHRA. Drug Safety Update (February 2015). Nitrofurantoin now contraindicated in most patients with an estimated glomerular filtration rate (eGFR) of less than 45 ml/min/1.73m2 Accessed via https://www.gov.uk/drug-safety-update/nitrofurantoin-now-contraindicated-in-most-patients-with-an-estimated-glomerular-filtration-rate-egfr-of-less-than-45-ml-min-1-73m2 Accessed 23/3/26
• MHRA. Drug Safety Update (April 2023) Nitrofurantoin: reminder of the risks of pulmonary and hepatic adverse drug reactions Accessed via https://www.gov.uk/drug-safety-update/nitrofurantoin-reminder-of-the-risks-of-pulmonary-and-hepatic-adverse-drug-reactions Accessed 23/3/26