What antibiotics are recommended for treating mastitis during breastfeeding?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: June 29, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the FDA Drug Label

Limited published data based on breast milk sampling reports that clindamycin appears in human breast milk in the range of less than 0.5 to 3.8 mcg/mL. Clindamycin has the potential to cause adverse effects on the breast-fed infant's gastrointestinal flora. If oral or intravenous clindamycin is required by a nursing mother, it is not a reason to discontinue breastfeeding, but an alternate drug may be preferred. Penicillins are excreted in breast milk. Caution should be exercised when penicillins are administered to a nursing woman.

Antibiotics for Mastitis during Breastfeeding:

  • Clindamycin may be used during breastfeeding, but monitor the infant for adverse effects on the gastrointestinal flora, such as diarrhea or candidiasis 1.
  • Dicloxacillin, a penicillin, is excreted in breast milk, and caution should be exercised when administering it to a nursing woman 2. Key Considerations:
  • The potential risks and benefits of antibiotic treatment should be weighed, and the most appropriate antibiotic should be chosen based on the severity of the mastitis and the individual patient's circumstances.
  • Monitoring of the breast-fed infant for possible adverse effects is recommended.

From the Research

For treating mastitis during breastfeeding, dicloxacillin or cephalexin are typically recommended as first-line antibiotics, usually at a dose of 500 mg four times daily for 10-14 days. These antibiotics are effective against Staphylococcus aureus, the most common bacterial cause of mastitis, while being safe for breastfeeding mothers and their infants 3, 4. The choice of antibiotic should be based on the severity of the infection and the patient's medical history, including any allergies to penicillin.

Some key points to consider when treating mastitis during breastfeeding include:

  • Completing the full course of antibiotics even if symptoms improve quickly
  • Continuing to breastfeed or express milk from the affected breast to prevent milk stasis and help clear the infection
  • Using warm compresses before feeding, gentle massage toward the nipple, and adequate rest and hydration to complement antibiotic therapy
  • Monitoring for signs of complications, such as an abscess or resistant infection, and seeking prompt medical reevaluation if symptoms do not improve within 48 hours of starting antibiotics or if the infection worsens.

It's also important to note that the transfer of dicloxacillin into human milk is minimal, with a relative infant dose (RID) of 0.03% 4. This suggests that dicloxacillin is a safe choice for breastfeeding mothers. However, as with any medication, it's essential to weigh the benefits and risks and to monitor the infant for any signs of adverse effects.

In cases where the patient is allergic to penicillin, alternative antibiotics such as clindamycin or azithromycin may be considered 3. Additionally, if the infection is severe or does not respond to initial treatment, further evaluation and adjustment of the treatment plan may be necessary. Overall, the goal of treatment should be to effectively manage the infection while supporting the continuation of breastfeeding and minimizing the risk of complications for both the mother and the infant 5.

References

Research

Management of mastitis in breastfeeding women.

American family physician, 2008

Research

Transfer of Dicloxacillin into Human Milk.

Breastfeeding medicine : the official journal of the Academy of Breastfeeding Medicine, 2020

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.