What is the recommended dose of Cefixime (Cephalosporin) for a typical adult patient with an uncomplicated bacterial infection for a 7-day treatment course?

Cefixime Dosing for 7-Day Treatment Course

For typical adult patients with uncomplicated bacterial infections, cefixime should be dosed at 400 mg orally once daily or 200 mg orally twice daily for 7 days, though this antibiotic has significant limitations and is NOT recommended as first-line therapy for most common infections.

Standard Adult Dosing

• The established dose is 400 mg once daily or 200 mg twice daily for respiratory and urinary tract infections 1, 2, 3
• Cefixime's 3-hour elimination half-life permits simplified once-daily or twice-daily dosing regimens 1
• Clinical trials demonstrate that 7-day courses are effective for acute exacerbations of chronic bronchitis and uncomplicated urinary tract infections 2, 4

Critical Limitations and Appropriate Use

Cefixime has poor activity against Staphylococcus aureus and is completely inactive against Pseudomonas aeruginosa and anaerobes 1, 5

Where Cefixime Should NOT Be Used:

• Dental infections: Completely inappropriate due to lack of anaerobic coverage 5
• Skin and soft tissue infections: Poor staphylococcal activity makes it unsuitable 1
• Serious or complicated infections: Limited spectrum requires alternative agents

Limited Appropriate Indications:

• Uncomplicated gonorrhea (alternative only): If ceftriaxone is unavailable, cefixime 400 mg as a single dose MUST be combined with azithromycin 1 g orally or doxycycline 100 mg twice daily for 7 days, with mandatory test-of-cure at 1 week 6, 7
• Uncomplicated urinary tract infections: 400 mg daily shows 94% cure rates 2
• Acute otitis media in children: 8 mg/kg daily demonstrates comparable efficacy to amoxicillin 1, 8
• Acute exacerbations of chronic bronchitis: 400 mg daily shows 98% cure/improvement rates 2, 4

Pediatric Dosing

• Standard dose: 8 mg/kg/day (maximum 400 mg/day) given once daily or divided twice daily 1, 8
• Treatment duration typically 7-10 days for respiratory infections 8

Common Pitfalls

• Do not use for polymicrobial infections: The narrow spectrum misses critical pathogens 5
• Diarrhea is common: Occurs in 16-24% of patients, usually mild and transient 1, 8
• For gonorrhea, never use as monotherapy: Always combine with azithromycin or doxycycline and perform test-of-cure 6
• Not suitable for serious infections: Reserve for uncomplicated outpatient cases only 1, 2

Preferred Alternatives

For most common bacterial infections, amoxicillin or amoxicillin-clavulanate provide superior coverage and should be considered first-line therapy 5