Can I use cefexime (Cefexime) 400 mg twice daily (bd) for urinary tract infection (UTI)?

Cefixime for Urinary Tract Infection Treatment

Cefixime 400 mg once daily is recommended for uncomplicated urinary tract infections, not twice daily (bd) as suggested in the question. 1

Appropriate Dosing for UTIs

Cefixime is FDA-approved for uncomplicated urinary tract infections with a recommended adult dosage of 400 mg daily as a single dose, not twice daily 1. The medication can be administered without regard to food and is effective against susceptible isolates of Escherichia coli and Proteus mirabilis, which are common UTI pathogens.

Dosing Considerations:

• Standard adult dose: 400 mg once daily 1
• Duration: Typically 7-10 days for uncomplicated UTIs
• Renal adjustment needed: For creatinine clearance <60 mL/min 1

Efficacy in UTI Treatment

Clinical studies have demonstrated cefixime's effectiveness in treating UTIs:

• 98% clinical effectiveness rate in acute uncomplicated cystitis 2
• 57% effectiveness in complicated UTIs 2
• Particularly effective against Enterobacteriaceae, which are common UTI pathogens 3

Position in Treatment Algorithm

While cefixime can be effective for UTIs, current guidelines do not position it as a first-line agent:

1. First-line options for uncomplicated UTIs include:

   • Nitrofurantoin (100 mg twice daily for 5 days) 4
   • Trimethoprim-sulfamethoxazole (160/800 mg twice daily for 3 days) 4

2. Beta-lactams (including cefixime):

   • Considered appropriate when first-line agents cannot be used 5
   • Generally have inferior efficacy and more adverse effects compared to other UTI antimicrobials 5
   • Should be used with caution for uncomplicated cystitis 5

Important Considerations and Cautions

Resistance Concerns

• Beta-lactams should be used cautiously due to concerns about efficacy and resistance 5
• Fluoroquinolones are preferred over cephalosporins for complicated UTIs when local resistance is <10% 5, 4

Adverse Effects

• Most common side effects are gastrointestinal (diarrhea, stool changes) 3
• Twice daily dosing (200 mg twice daily) may have fewer gastrointestinal side effects than once daily dosing (400 mg) 6, but this contradicts the FDA-approved dosing recommendation

Special Populations

• Renal impairment: Dose adjustment required for creatinine clearance <60 mL/min 1
• Pediatric patients: Weight-based dosing of 8 mg/kg/day 1

Bottom Line

While cefixime 400 mg can be used for UTIs, the correct dosing is once daily, not twice daily as suggested in the question. Additionally, it should be considered an alternative rather than first-line therapy for uncomplicated UTIs, with nitrofurantoin and trimethoprim-sulfamethoxazole being preferred first-line options when susceptibility is known or local resistance patterns permit.

If you choose to use cefixime for a UTI, follow the FDA-approved dosing of 400 mg once daily, and consider obtaining a urine culture to ensure the causative organism is susceptible.