What is the dose and duration of doxycycline for treating wound infections?

Doxycycline Dosing for Wound Infections

For wound infections, doxycycline should be dosed at 100 mg twice daily for 7-14 days, based on clinical response and infection severity. 1, 2, 3

Standard Adult Dosing Regimen

• The FDA-approved dosing is 200 mg on the first day (100 mg every 12 hours), followed by 100 mg daily maintenance dosing. 3
• However, for wound infections specifically, the Infectious Diseases Society of America recommends 100 mg twice daily (not once daily maintenance) for the entire 7-14 day treatment course to achieve adequate antimicrobial activity for clinical cure. 1, 2
• The twice-daily dosing throughout treatment is critical—single daily maintenance dosing is insufficient for active wound infections. 2

Treatment Duration by Infection Severity

• Mild to moderate wound infections: 7-10 days of treatment 1, 2
• Severe infections or deep tissue involvement: extend to 14 days 1, 2
• Hand/finger wounds carry highest complication risk and warrant the full 14-day course due to risk of tendosynovitis, septic arthritis, and osteomyelitis. 4

Pediatric Dosing

• Children ≥8 years and ≥45 kg: use adult dosing (100 mg twice daily) 1
• Children ≥8 years and <45 kg: 2.2 mg/kg every 12 hours 1
• Children <8 years: doxycycline is contraindicated due to permanent tooth discoloration and enamel hypoplasia risk. 5, 1

Critical Administration Guidelines

• Take with a full glass of water while sitting or standing to reduce esophageal irritation and ulceration risk. 5, 3
• Avoid lying down for 1 hour after administration. 1
• May be taken with food or milk if gastric irritation occurs—absorption is not significantly affected. 3
• Separate dosing by at least 2 hours from dairy products, antacids, and supplements containing calcium, iron, magnesium, or sodium bicarbonate (except when taking with food for GI tolerance). 1

Coverage Considerations and Limitations

• Doxycycline provides excellent coverage for many wound pathogens but has important gaps: 2, 4

  • Good activity against: Staphylococci (including MRSA), many gram-negatives, Pasteurella multocida (animal bites), anaerobes
  • Resistance concern: Some streptococci may be resistant 2, 4

• For polymicrobial wound infections (especially animal bites), amoxicillin-clavulanate is superior first-line therapy due to broader coverage including resistant streptococci and anaerobes. 4

When Doxycycline May Fail

• Doxycycline is bacteriostatic, not bactericidal—this may be insufficient for established deep tissue infections or abscesses. 4
• If clinical improvement does not occur within 48-72 hours, consider:
  • Surgical consultation for incision and drainage if abscess or deep space infection present 4
  • Switch to amoxicillin-clavulanate 875/125 mg twice daily 4
  • Add TMP-SMX if MRSA suspected 4

Special Populations

• Renal impairment: No dosage adjustment required 1, 3
• Pregnancy: Generally contraindicated, but may be used for life-threatening infections when benefits outweigh risks 1, 2
• Breastfeeding: Use with caution; consider alternatives 2

Common Pitfalls to Avoid

• Do not use inadequate duration (<7 days)—this leads to treatment failure. 2
• Do not use once-daily maintenance dosing for active infections—twice-daily dosing is required throughout treatment. 2, 3
• Do not use doxycycline monotherapy for polymicrobial animal bite wounds—amoxicillin-clavulanate is preferred. 4
• Do not delay surgical evaluation if deep infection or abscess suspected—antibiotics alone are insufficient. 4