What is the dosage and usage of Ofloxacin (fluoroquinolone antibiotic) for treating bacterial infections?

Ofloxacin Dosage and Usage for Bacterial Infections

For treating bacterial infections, ofloxacin is typically administered at 200-400 mg orally every 12 hours, with specific dosages depending on the type of infection being treated. 1

Standard Dosing Regimens by Infection Type

• Respiratory Tract Infections:

  • Acute bacterial exacerbation of chronic bronchitis: 400 mg every 12 hours for 10 days (800 mg daily) 1
  • Community-acquired pneumonia: 400 mg every 12 hours for 10 days (800 mg daily) 1

• Skin and Skin Structure Infections:

  • Uncomplicated infections: 400 mg every 12 hours for 10 days (800 mg daily) 1

• Sexually Transmitted Infections:

  • Acute, uncomplicated gonorrhea: 400 mg as a single dose 2, 1
  • Nongonococcal cervicitis/urethritis due to C. trachomatis: 300 mg every 12 hours for 7 days 1
  • Mixed infection of urethra and cervix due to C. trachomatis and N. gonorrhoeae: 300 mg every 12 hours for 7 days 1
  • Acute pelvic inflammatory disease: 400 mg every 12 hours for 10-14 days 1

• Urinary Tract Infections:

  • Uncomplicated cystitis due to E. coli or K. pneumoniae: 200 mg every 12 hours for 3 days 1
  • Uncomplicated cystitis due to other approved pathogens: 200 mg every 12 hours for 7 days 1
  • Complicated UTIs: 200 mg every 12 hours for 10 days 1
  • Prostatitis due to E. coli: 300 mg every 12 hours for 6 weeks 1, 3

Special Population Considerations

• Patients with Impaired Renal Function: Dosage adjustment required based on creatinine clearance 1:

  • Creatinine clearance 20-50 mL/min: Normal unit dose given once daily (every 24 hours)
  • Creatinine clearance <20 mL/min: Half the usual recommended unit dose given once daily

• Patients with Cirrhosis: Maximum daily dose should not exceed 400 mg due to reduced excretion in patients with severe liver function disorders 1

Administration Guidelines

• Antacids containing calcium, magnesium, or aluminum; sucralfate; divalent or trivalent cations (iron); multivitamins containing zinc; or didanosine should not be taken within 2 hours before or after taking ofloxacin 1

Efficacy Considerations

• Ofloxacin achieves good concentrations in genitourinary tract tissues and fluids, making it particularly effective for urinary tract infections 4
• Bacteriological response rates exceed 80% in uncomplicated UTIs and 70% in complicated UTIs 4
• For prostatitis, ofloxacin has shown 100% microbiologic cure rates in preliminary studies 3

Antimicrobial Spectrum

• Good activity against most Enterobacteriaceae, Staphylococcus saprophyticus, methicillin-susceptible S. aureus, N. gonorrhoeae, and C. trachomatis 4
• Limited activity against enterococci, Serratia marcescens, Pseudomonas aeruginosa, and many anaerobes 4
• High concentrations achieved in urine ensure activity against most urinary tract pathogens 4, 5

Resistance Concerns

• Quinolone-resistant N. gonorrhoeae (QRNG) has been reported in various parts of the world 2
• Resistance of P. aeruginosa to ofloxacin can develop during treatment (reported in 15% of isolates) 6
• In areas with high resistance rates, cephalosporins may be preferred over fluoroquinolones 2

Common Adverse Effects

• Most common adverse events are gastrointestinal, neurological, and dermatological 4
• Insomnia has been reported (27% in one study) and may respond to dose reduction 6
• Lower incidence of photosensitivity and tendinitis compared to some other fluoroquinolones 4

Ofloxacin's bactericidal activity, broad spectrum coverage, and favorable pharmacokinetics make it an effective option for various bacterial infections when used according to appropriate dosing guidelines and with consideration of local resistance patterns.