From the Guidelines
Macrobid (nitrofurantoin) should be avoided in patients with CKD stage 3, particularly when eGFR is less than 45 mL/min/1.73m², due to the risk of toxicity and decreased efficacy 1. For patients with CKD stage 3a (eGFR 45-59 mL/min/1.73m²), short courses (3-7 days) may be considered with caution for uncomplicated urinary tract infections if benefits outweigh risks and no alternatives exist. However, for patients with CKD stage 3b (eGFR 30-44 mL/min/1.73m²), Macrobid should generally be avoided. The concern with using Macrobid in reduced kidney function is twofold: decreased efficacy due to insufficient urinary concentration of the drug, and increased risk of toxicity from accumulation of the drug and its metabolites in the bloodstream. Some key points to consider when prescribing antibiotics in CKD patients include:
- Avoiding nephrotoxic drugs such as aminoglycosides and tetracyclines 1
- Considering alternative antibiotics such as trimethoprim-sulfamethoxazole (with dose adjustment), cephalexin, amoxicillin-clavulanate, or fluoroquinolones (with appropriate dose adjustments based on kidney function)
- Monitoring patients with CKD for adverse effects including pulmonary reactions, hepatotoxicity, and peripheral neuropathy, which may be more common with impaired kidney function. It is essential to weigh the benefits and risks of using Macrobid in patients with CKD stage 3 and consider alternative treatment options to minimize the risk of adverse effects. In general, the choice of antibiotics and dose adjustments should be made based on comments from the patient’s nephrologist before the treatment in order to decrease the side effects from CKD 1.
From the Research
Macrobid in CKD Stage 3
- The use of Macrobid (nitrofurantoin) in patients with chronic kidney disease (CKD) stage 3 is a topic of interest, with some studies suggesting that it may be safe to use in patients with a creatinine clearance of 40 mL/min or higher 2.
- A study published in 2013 found that the contraindication of nitrofurantoin in patients with a creatinine clearance below 60 mL/min was not supported by strong evidence, and that the drug may be effective in patients with a creatinine clearance of 40 mL/min or higher 2.
- Another study published in 2015 found that the use of nitrofurantoin to treat urinary tract infections in older women with reduced kidney function was not associated with an increased risk of treatment failure, even in those with a relatively low estimated glomerular filtration rate 3.
- A systematic review of randomized controlled trials published in 2021 found that nitrofurantoin was at least comparable to other treatments for uncomplicated urinary tract infections in terms of efficacy, and that patients taking nitrofurantoin reported fewer side effects than those taking other drugs 4.
- However, it is important to note that the evidence is not yet conclusive, and more robust research is needed to fully understand the safety and efficacy of Macrobid in patients with CKD stage 3 2, 4.
- In terms of dosing, a study published in 2020 emphasized the importance of adapting antibiotic dosages to renal function to prevent adverse effects, and provided guidance on dose adjustments for patients with chronic kidney disease 5.
- Another study published in 2019 highlighted the challenges of antibiotic dosing in patients with CKD and end-stage renal disease, and emphasized the need for careful evaluation of renal function and monitoring of antibiotic efficacy and safety 6.