Ciprofloxacin Dosing Regimens for Bacterial Infections
The typical dosing regimen for ciprofloxacin varies by infection type, with oral dosing generally ranging from 250-750 mg twice daily and intravenous dosing of 400 mg every 8-12 hours, with adjustments needed for renal impairment. 1
Adult Oral Dosing
| Infection Type | Dosage | Duration |
|---|---|---|
| Uncomplicated UTI | 250-500 mg twice daily | 3 days |
| Complicated UTI/Pyelonephritis | 500 mg twice daily | 7-14 days |
| Respiratory infections | 500-750 mg twice daily | 7-14 days |
| Skin/soft tissue infections | 500-750 mg twice daily | 7-14 days |
| Bone/joint infections | 500-750 mg twice daily | 4-6 weeks |
| Infectious diarrhea | 500 mg twice daily | 5-7 days |
| Typhoid fever | 500 mg twice daily | 10 days |
| Uncomplicated gonorrhea | 500 mg as single dose | One time |
Adult Intravenous Dosing
| Infection Type | Dosage | Duration |
|---|---|---|
| Complicated UTI/Pyelonephritis | 400 mg every 12 hours | 7-14 days |
| Severe respiratory infections | 400 mg every 8 hours | 7-14 days |
| Skin/soft tissue infections | 400 mg every 12 hours | 7-14 days |
| Bone/joint infections | 400 mg every 8-12 hours | 4-6 weeks |
| Intra-abdominal infections | 400 mg every 12 hours (with metronidazole) | 7-14 days |
Renal Dose Adjustments
- Normal renal function (CrCl >90 mL/min): Standard dosing
- Moderate impairment (CrCl 30-60 mL/min): 400 mg IV every 12 hours or 50% of oral dose
- Severe impairment (CrCl <30 mL/min): 400 mg IV every 24 hours or 50% of oral dose 2
Special Populations
Pediatric Dosing
- Generally not first-line therapy in children due to potential joint/cartilage toxicity
- When necessary: 10-20 mg/kg PO every 12 hours (max 750 mg/dose) or 10 mg/kg IV every 8-12 hours (max 400 mg/dose) 3
Elderly
- No specific dose adjustment needed based on age alone
- Adjust based on renal function and comorbidities
Specific Infection Protocols
Urinary Tract Infections
- Uncomplicated cystitis: 250 mg PO twice daily for 3 days
- Complicated UTI/Pyelonephritis: 500 mg PO twice daily for 7-14 days or 400 mg IV every 12 hours 3
Gonorrhea
- 500 mg PO as a single dose (though no longer recommended as first-line due to resistance) 3
Endocarditis (HACEK organisms)
- 500 mg PO twice daily or 400 mg IV twice daily for 4 weeks 3
Skin and Soft Tissue Infections
- 400 mg IV every 12 hours (often combined with metronidazole for polymicrobial infections) 3
Important Considerations and Precautions
Resistance patterns: Local resistance patterns should guide empiric therapy choices. Fluoroquinolone resistance is increasing in many regions.
Drug interactions: Avoid concurrent administration with:
- Magnesium/aluminum antacids
- Sucralfate
- Products containing calcium, iron, or zinc
- Tizanidine (contraindicated)
Timing with other medications: Take ciprofloxacin 2 hours before or 6 hours after interacting products.
Adverse effects to monitor:
- Tendinopathy/tendon rupture (higher risk in elderly, those on corticosteroids)
- CNS effects (dizziness, confusion, headache)
- QT prolongation
- Photosensitivity
- C. difficile-associated diarrhea
Hydration: Patients should drink fluids liberally to prevent crystalluria.
Renal function: Dose adjustment required for CrCl <60 mL/min.
Common Pitfalls to Avoid
Overuse in uncomplicated infections: Reserve for appropriate indications to minimize resistance development.
Inadequate dosing for severe infections: Higher doses (750 mg PO or 400 mg IV q8h) are needed for severe infections.
Failure to adjust for renal function: Can lead to toxicity in patients with impaired renal function.
Inappropriate use in children: Not first-line therapy in pediatric patients due to risk of arthropathy.
Missing drug interactions: Especially with antacids, minerals, and dairy products, which can significantly reduce absorption.
Inadequate duration: Too short a course may lead to treatment failure and resistance development.