Is penicillin (antibiotic) safe to use during breastfeeding?

Penicillin Safety During Breastfeeding

Penicillin antibiotics are safe to use during breastfeeding and pose minimal risk to nursing infants. 1

Safety Profile of Penicillins During Breastfeeding

• Penicillins (including amoxicillin, amoxicillin/clavulanic acid, and other penicillin derivatives) are considered compatible with breastfeeding and can be safely used by nursing mothers 1
• These antibiotics have limited transfer into breast milk and have low oral bioavailability in infants, meaning minimal absorption occurs even if present in milk 2
• The relative infant dose (RID) for penicillins like dicloxacillin has been measured at only 0.03% of the maternal dose, well below the theoretical level of concern of 10% 3

Specific Penicillin Antibiotics in Breastfeeding

• Amoxicillin and amoxicillin/clavulanic acid are explicitly recommended as safe options for breastfeeding mothers requiring antibiotic therapy 1
• Penicillins have long been considered safe for breastfeeding mothers and their infants based on extensive clinical experience 2
• For hidradenitis suppurativa specifically, guidelines suggest using oral amoxicillin/clavulanic acid in breastfeeding patients who require systemic antibiotics 1

Considerations When Using Penicillins During Breastfeeding

• While penicillins are generally safe, they may cause mild and transient effects in some nursing infants:
  • Potential modification of bowel flora, which could lead to mild diarrhea 2
  • Possible allergic sensitization (though extremely rare) 3
• To minimize infant exposure:
  • Consider taking medication immediately after breastfeeding to minimize peak concentration in milk 4
  • Monitor the infant for unusual symptoms such as rash, diarrhea, or changes in feeding patterns 4

Comparison with Other Antibiotics

• β-lactam antibiotics (including penicillins) are generally considered safer during breastfeeding compared to:
  • Tetracyclines (such as doxycycline), which should be limited to short courses (≤3 weeks) if no alternatives are available 1
  • Fluoroquinolones (such as ciprofloxacin), which should not be first-line treatment but can be used if specifically indicated 2
• For breastfeeding mothers with penicillin allergies, cephalosporins are often a safe alternative unless there is a history of anaphylaxis 1

Clinical Recommendations

• When treating infections in breastfeeding mothers, penicillins should be considered as first-line agents when appropriate for the infection 1, 2
• For mothers concerned about antibiotic use while breastfeeding, it's important to emphasize that untreated maternal infections pose a greater risk to both mother and infant than the minimal exposure to penicillins through breast milk 5
• The benefits of continued breastfeeding while on penicillin therapy outweigh the minimal risks to the infant 5, 2