Doxycycline Dosing and Duration for Skin Infections
For standard skin and soft tissue infections in adults, doxycycline should be administered at 100 mg twice daily for 7-14 days, with duration based on clinical response. 1, 2
Adult Dosing Recommendations
- Standard dose for uncomplicated skin infections: 100 mg orally twice daily 1, 2
- Duration for most bacterial skin infections: 7-14 days, continuing until resolution of erythema, warmth, and induration 1, 2
- For MRSA skin infections: 100 mg twice daily orally 1, 2
- For non-purulent cellulitis (presumed streptococcal): 100 mg twice daily with comparable efficacy to beta-lactams 3
Pediatric Dosing Considerations
- Not recommended for children under 8 years of age due to risk of dental staining 1, 2
- For children >8 years and >45 kg: 100 mg every 12 hours 1
- For children >8 years and ≤45 kg: 2.2 mg/kg every 12 hours 1
Duration of Therapy
- Standard duration for most skin infections: 7-14 days 1, 2
- Recent evidence suggests 7 days may be sufficient for certain infections like erythema migrans (Lyme disease) 4
- Treatment should continue until clinical improvement is observed, with resolution of erythema, warmth, and induration 2
Special Considerations
- For immunocompromised patients or severe infections, longer courses may be needed 1
- In areas with high streptococcal prevalence, some guidelines recommend combining doxycycline with a beta-lactam antibiotic for more complete coverage 2
- Low-dose doxycycline (20-40 mg/day) has anti-inflammatory properties that may be beneficial in certain chronic skin conditions, but is not appropriate for acute bacterial infections 5, 6
Potential Adverse Effects
- Gastrointestinal discomfort (reported in 21.4% of patients) 7
- Photosensitivity (reported in some patients) 7
- To minimize GI side effects, doxycycline should be taken with food 7
Clinical Pearls
- Doxycycline is particularly useful for MRSA skin infections when oral therapy is appropriate 1, 2
- Clinical response should guide duration - continue treatment until resolution of signs and symptoms 1, 2
- For severe infections or those with systemic involvement, consider initial IV therapy before transitioning to oral doxycycline 1
- Recent evidence suggests doxycycline is effective for non-purulent (presumed streptococcal) skin infections with low failure rates (6%) comparable to cephalexin 3