From the Guidelines
Nitrofurantoin is recommended at a dose of 100 mg twice daily for 5 days for the treatment of uncomplicated urinary tract infections.
Key Points
- The recommended dose and frequency of Nitrofurantoin is 100 mg twice daily for 5 days 1.
- This regimen has been shown to have comparable efficacy to 3 days of trimethoprim-sulfamethoxazole 1.
- Nitrofurantoin has minimal resistance and propensity for collateral damage, making it an appropriate choice for therapy 1.
- The clinical cure rate with Nitrofurantoin is 88% - 93% and the bacterial cure rate is 81% - 92% 1.
- Other studies have also recommended Nitrofurantoin 100 mg PO every 6 h for the treatment of uncomplicated urinary tract infections due to multidrug-resistant organisms, but this is based on weak recommendation and very low quality of evidence 1.
- However, in the context of real-life clinical medicine, the dose of 100 mg twice daily for 5 days is preferred due to its established efficacy and safety profile.
From the Research
Recommended Dose and Frequency of Nitrofurantoin
- The recommended dose and frequency of Nitrofurantoin vary depending on the specific use case, such as treatment or prophylaxis of urinary tract infections (UTIs) 2, 3, 4, 5, 6.
- For the treatment of uncomplicated lower urinary tract infections, a dose of 100 mg three times a day for 5 days is commonly used 2, 3.
- A study comparing 5-day Nitrofurantoin with single-dose Fosfomycin found that Nitrofurantoin resulted in a significantly greater likelihood of clinical and microbiologic resolution at 28 days after therapy completion 3.
- For prophylaxis of UTIs, a daily dose of 50 mg or 100 mg is used, with some studies suggesting that 50 mg may have a better safety profile 4, 6.
- A cohort study found that daily prophylaxis with 100 mg instead of 50 mg Nitrofurantoin was associated with an equivalent hazard on UTI or pyelonephritis, but a higher hazard on cough, dyspnea, and nausea 6.
Special Considerations
- In patients with renal insufficiency, Nitrofurantoin may still be effective, but its use should be carefully considered, as its efficacy may be decreased in patients with severe renal impairment 5.
- The duration of Nitrofurantoin prophylaxis may also impact its safety, with longer durations potentially increasing the risk of severe adverse effects 4.