Mastitis Organism-Specific Therapy 

Updated: Dec 17, 2014
  • Author: Andrew C Miller, MD; Chief Editor: Thomas E Herchline, MD  more...
  • Print

Specific Organisms and Therapeutic Regimens

Organism-specific regimens for mastitis are provided below, including those for Staphylococcus aureus, coagulase-negative staphylococci, staphylococci, streptococci, and Peptostreptococcus.

Methicillin-sensitive S aureus or coagulase-negative staphylococci

See the list below:

Methicillin-resistant S aureus or coagulase-negative staphylococci

See the list below:

  • TMP-SMZ 160 mg/800 mg 1 DS tablet BID for 10-14d or
  • Clindamycin 600 mg IV q8h or 300 mg PO TID for 10-14d or
  • Vancomycin 1 g IV q12h for 10-14d
  • When clinical improvement is apparent, transition the patient from IV to oral antibiotics for completion of a 10-14d course [1, 2, 3, 4, 5]

Streptococci or Peptostreptococcus

See the list below:

  • Dicloxacillin 500 mg QID for 10-14d or
  • Cephalexin 500 mg PO QID for 10-14d or
  • Amoxicillin-clavulanate 500 mg PO TID for 10-14d or
  • Clindamycin 600 mg IV q8h or 300 mg PO TID for 10-14d [1, 2, 3]

Special considerations

See the list below:

  • Milk culture is not specific; 1 mL of normal breast milk may contain >1000 colonies of skin flora
  • Milk stasis (as with skipped or incomplete feedings) is a major risk factor for mastitis