Nitrofurantoin update

Nitrofurantoin was previously contraindicated in patients with a creatinine clearance of less than 60 ml/min.

The MHRA have reviewed the evidence for this contraindication in the context of increasing antibiotic resistance of lower urinary tract pathogens to standard therapy (trimethoprim and amoxicillin). They have also considered the risk of Clostridium difficile colitis associated with the widespread use of alternative broad-spectrum antibiotics (cephalosporins and fluoroquinolones).

The MHRA have concluded that the existing contraindication is no longer supported and that the available evidence justified a revised contraindication against use in patients with an eGFR of less than 45 ml/min.

N.B. Antibiotic treatment of asymptomatic bacteriuria is not advised except during pregnancy and other special circumstances

Advice for healthcare professionals

• Nitrofurantoin is contraindicated in patients with an estimated glomerular filtration rate (eGFR) of less than 45 ml/min.
• Nitrofurantoin should not be used to treat sepsis syndrome secondary to urinary tract infection or suspected upper urinary tract infections
• 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 to such patients to treat lower urinary tract infection with suspected or proven multidrug resistant pathogens when the benefits of nitrofurantoin are considered to outweigh the risks of side effects.
• Consider checking renal function when choosing to treat with nitrofurantoin, especially in the elderly.
• Closely monitor for signs of pulmonary, hepatic, neurological, hematological, and gastrointestinal side effects during treatment, as advised in the summary of product characteristics