Staphylococcus aureus

Moderate to Severe Cellulitis

First Line

IV Flucloxacillin5 1-2g  6 hourly

Stepping down to:

ORAL Flucloxacillin 1g 6 hourly


Penicillin Allergy or if MRSA positive

IV Vancomycin3

Stepping down to:

ORAL Doxycyline2 100mg 12 hourly

Total Duration (IV + Oral): 10-14 days

Limited soft tissue infection

First Line

ORAL Flucloxacillin 1g 6 hourly


Penicillin allergy

ORAL Clarithromycin1 500mg 12 hourly

Total duration: 7 days


Doses may need to be adjusted in renal impairment. Always check BNF for interactions. Seek advice if patient pregnant

Drug specific guidance:

  1. Check interactions in the BNF. Caution may prolong QT interval.
  2. Avoid Doxycycline and Co-trimoxazole if pregnant or breast feeding
  3. Gentamicin/Vancomycin refer to online calculators
  4. ALERT antibiotic needs ALERT form
  5. Monitor sodium
  6. See CURB65 definition
  7. Reference: The Renal Drug Handbook 4th Edition, 2014