From the Guidelines
Nitrofurantoin should not be used in patients with severely impaired renal function, including those on dialysis, due to the risk of toxic metabolite accumulation and peripheral neuritis. The use of nitrofurantoin in patients with impaired renal function is problematic because the drug is primarily eliminated by the kidneys and requires adequate renal function to concentrate in the urine and effectively treat urinary tract infections 1. In patients with severely impaired renal function, the drug can accumulate to toxic levels, leading to adverse effects such as peripheral neuropathy and pulmonary toxicity.
Key Considerations
- Nitrofurantoin requires a creatinine clearance of >30 mL/min to be effective and safe, which is often not the case in patients with severely impaired renal function 1.
- The risk of toxic metabolite accumulation and peripheral neuritis associated with nitrofurantoin use in patients with impaired renal function outweighs any potential benefits 1.
- Alternative antibiotics, such as trimethoprim-sulfamethoxazole, ciprofloxacin, or cephalexin, can be used instead, with dose adjustments as needed, depending on the specific infection and local resistance patterns.
Recommended Approach
- Avoid using nitrofurantoin in patients with severely impaired renal function, including those on dialysis.
- Consult with a nephrologist to determine the best antibiotic option and dose adjustment for patients with impaired renal function.
- Consider alternative antibiotics that are less dependent on renal elimination or can be appropriately dose-adjusted for patients with impaired renal function.
From the Research
Nitrofurantoin Use in Impaired Renal Function
- Nitrofurantoin is contraindicated in patients with renal impairment of each degree, according to some studies 2.
- However, other studies suggest that nitrofurantoin can be used in patients with mild or moderate reductions in estimated glomerular filtration rate (eGFR) 3, 4.
- A study found that nitrofurantoin was effective in treating acute uncomplicated cystitis in hospitalized adults with renal insufficiency (CrCl < 60 ml/min), with a cure rate of 69% 4.
- Another study suggested that the contraindication of nitrofurantoin in patients with a CrCl below 60 mL/min may not be supported by evidence, and that the drug could be considered for use in patients with a CrCl of 40 mL/min or higher 5.
Recommended Dose
- The recommended dose of nitrofurantoin is not explicitly stated in the provided studies for patients with impaired renal function.
- However, one study suggests that nitrofurantoin can be used at the standard dose in patients with a CrCl of 30-60 ml/min, but may not be effective in patients with a CrCl < 30 ml/min 4.
- It is essential to note that the use of nitrofurantoin in patients with impaired renal function should be approached with caution, and the dosage should be adjusted according to the patient's renal function and the severity of the infection.
Safety Considerations
- Nitrofurantoin can cause serious side effects, such as pulmonary reactions and polyneuropathy, especially in patients with impaired renal function 2, 6.
- Patients with impaired renal function may be at increased risk of developing these side effects, and the drug should be used with caution in this population 6.