From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
For a 92-year-old male with a UTI, nitrofurantoin (Macrobid) 100mg twice daily for 7 days is recommended as first-line therapy, assuming normal renal function and no allergies, due to its efficacy and lower resistance rates compared to other antibiotics, as supported by the most recent study 1. The choice of antibiotic should be guided by local resistance patterns, patient's medication history, and comorbidities.
- Nitrofurantoin is effective against common uropathogens, including Escherichia coli, and has lower resistance rates compared to trimethoprim-sulfamethoxazole and fluoroquinolones 1.
- Alternatives may include fosfomycin, which also has low resistance rates, but its use may be limited by availability and cost.
- Fluoroquinolones, such as ciprofloxacin, may be considered in cases of complicated UTI or suspected resistance, but they carry a higher risk of adverse effects in the elderly.
- Elderly patients often present with atypical symptoms, such as confusion, rather than classic dysuria, and adequate hydration is essential during treatment.
- Dosage adjustments may be necessary based on renal function, which commonly declines with age, and treatment should begin promptly after obtaining a urine culture to prevent progression to more serious infection, particularly important in this vulnerable age group.
- The most recent study 1 highlights the importance of knowledge of local epidemiology to inform the selection of appropriate empirical antibiotic regimens, and nitrofurantoin is a suitable option in areas with high resistance rates to commonly used antibiotics.