What are alternative antibiotics for Urinary Tract Infection (UTI) suppression in patients resistant to Macrobid (Nitrofurantoin) and Keflex (Cephalexin)?

From the Guidelines

For patients resistant to Nitrofurantoin (Macrobid) and Cephalexin (Keflex), the most effective alternative antibiotic for UTI suppression is Trimethoprim-sulfamethoxazole (Bactrim, Septra) at 40/200 mg daily or three times weekly, as it has a high efficacy rate of 93% and is recommended by the Infectious Diseases Society of America and the European Society for Microbiology and Infectious Diseases 1. When considering alternative antibiotics, it's essential to take into account the patient's specific needs and the potential side effects of each medication.

• Other options for UTI suppression include Fosfomycin (Monurol) at 3g every 10 days, which has a clinical efficacy rate of 91% and is active against multidrug-resistant pathogens, including vancomycin-resistant enterococci (VRE), methicillin-resistant S. aureus (MRSA), and extended-spectrum β-lactamase (ESBL)–producing gram-negative rods 1.
• Ciprofloxacin (250-500 mg daily) is another option, with a high efficacy rate of 90%, but it should be reserved for important uses other than acute cystitis due to its propensity for collateral damage 1.
• Amoxicillin-clavulanate (250-500 mg daily) and Methenamine hippurate (1g twice daily) are also alternatives, but their efficacy rates are lower, and they may have more adverse effects 1. It's crucial to select an antibiotic based on urine culture results and antibiotic susceptibility testing to ensure effectiveness and minimize the risk of resistance development.
• Patients should maintain adequate hydration, urinate frequently, and consider cranberry products as adjunctive measures to prevent UTIs.
• Regular monitoring for specific side effects, such as periodic blood work to check kidney function and blood counts for TMP-SMX, is necessary to ensure safe and effective treatment.
• Antibiotic rotation may be necessary if resistance develops during long-term suppression therapy, and the mechanism of suppression involves maintaining a constant low level of antibiotic in the urinary tract to prevent bacterial colonization and multiplication.

From the FDA Drug Label

The FDA drug label does not answer the question about alternative antibiotics for Urinary Tract Infection (UTI) suppression in patients resistant to Macrobid (Nitrofurantoin) and Keflex (Cephalexin) directly. The FDA drug label does not answer the question.

From the Research

Alternative Antibiotics for UTI Suppression

In patients resistant to Macrobid (Nitrofurantoin) and Keflex (Cephalexin), alternative antibiotics can be considered for Urinary Tract Infection (UTI) suppression.

• First-line options: Fosfomycin, pivmecillinam, and amoxicillin-clavulanate are potential alternatives 2, 3, 4.
• Second-line options: Oral cephalosporins such as cefixime, fluoroquinolones, and β-lactams like piperacillin-tazobactam can be considered 2.
• ESBL-producing Enterobacteriaceae: Fosfomycin, pivmecillinam, amoxicillin-clavulanate, finafloxacin, and sitafloxacin are treatment options 2, 3.
• Carbapenem-resistant Enterobacteriaceae (CRE): Ceftazidime-avibactam, meropenem/vaborbactam, imipenem/cilastatin-relebactam, colistin, fosfomycin, aztreonam, and cefiderocol are potential treatment options 2.
• Multidrug-resistant (MDR)-Pseudomonas spp.: Fluoroquinolones, ceftazidime, cefepime, piperacillin-tazobactam, carbapenems, and fosfomycin are alternative antibiotics 2.

Susceptibility Rates

The susceptibility rates of various antibiotics against common uropathogens are:

• Fosfomycin: 96% against ESBL-producing E. coli, 81% against vancomycin-resistant E. faecium, and 90% against E. coli 3, 5, 6.
• Piperacillin-tazobactam: 96% against E. coli 6.
• Imipenem and meropenem: 97% against E. coli 6.
• Cefoperazone/sulbactam: 97% against E. coli 6.