What is the recommended dosage of doxycycline (tetracycline antibiotic) for treating skin infections?

Doxycycline Dosage for Skin Infections

The recommended dosage of doxycycline for treating skin infections in adults is 100 mg twice daily. 1, 2, 3

Standard Dosing Regimen

• Adults: 100 mg twice daily 1, 3

  • Initial dose may be 200 mg on the first day (100 mg every 12 hours), followed by maintenance dose of 100 mg twice daily 3
  • Treatment duration: 7-14 days for most skin infections 1, 2

• Children (>8 years of age):

  • ≤45 kg: 2.2 mg/kg every 12 hours 1, 3

  • 45 kg: 100 mg every 12 hours (adult dose) 1, 3

  • Not recommended for children under 8 years due to risk of dental staining 1, 2

Specific Skin Infection Types and Duration

1. Uncomplicated skin infections:

   • 100 mg twice daily for 7-10 days 1, 2

2. Complicated skin infections:

   • 100 mg twice daily for 7-14 days 1, 2

3. Specific infections with established protocols:

   • Bubonic plague: 100 mg twice daily 1
   • Mild tularemia: 100 mg twice daily 1
   • Cutaneous anthrax: 100 mg twice daily for 60 days 1

Clinical Considerations

• Administration: Take with adequate fluid to reduce risk of esophageal irritation 3

• Food interactions: Can be given with food or milk if gastric irritation occurs; absorption is not markedly influenced by simultaneous food intake 3

• Contraindications:

  • Pregnancy (especially after first trimester) due to risk of teratogenicity 1, 2
  • Children under 8 years due to dental staining 2

• Common side effects:

  • Gastrointestinal discomfort (8.6-21.4% of patients) 4
  • Photosensitivity 4

Antimicrobial Considerations

• Doxycycline is effective against many skin pathogens including staphylococci, streptococci, and anaerobes 1, 2
• It has good activity against Eikenella species and anaerobes, though some streptococci may be resistant 1
• For MRSA infections, doxycycline is an alternative when first-line agents cannot be used 1

Important Caveats

• For severe skin infections or those with systemic involvement, consider initial IV therapy or combination therapy 1
• Monitor for clinical improvement within 48-72 hours; if no improvement, reassess diagnosis or consider alternative therapy 2
• In areas with high MRSA prevalence, consider combination with other agents or alternative therapy based on local susceptibility patterns 1
• Low-dose doxycycline (20 mg twice daily) has been studied for inflammatory skin conditions like acne but is not recommended for treating infectious processes 5, 6

Doxycycline remains an effective option for skin and soft tissue infections, particularly when beta-lactam antibiotics cannot be used or when coverage for atypical organisms is needed.