What antibiotic can a breastfeeding patient take?

Safe Antibiotics for Breastfeeding Patients

Breastfeeding patients requiring antibiotics should use amoxicillin, amoxicillin/clavulanic acid, or cephalosporins as first-line options, as these β-lactam antibiotics are explicitly recommended as safe and compatible with breastfeeding. 1, 2, 3

First-Line Safe Antibiotics

Penicillins and cephalosporins are the preferred first-line choices:

• Amoxicillin is classified as FDA Category B and explicitly "compatible" with breastfeeding by multiple international guidelines 2, 3
• Amoxicillin/clavulanic acid (Augmentin) is strongly recommended as safe and effective during breastfeeding, with high-quality evidence supporting its use 4, 1, 2, 3
• Cephalosporins (such as cephalexin and ceftriaxone) are considered "compatible" with breastfeeding and particularly recommended for skin and soft tissue infections 1, 2
• These β-lactam antibiotics appear in breast milk at low concentrations and have minimal impact on nursing infants 1, 2

Additional Safe Antibiotic Options

Macrolides and other alternatives can be used when β-lactams are not appropriate:

• Erythromycin is suggested as safe, particularly for penicillin-allergic patients 4, 2
• Azithromycin is classified as "probably safe" but should ideally be avoided during the first 13 days postpartum due to a very low risk of hypertrophic pyloric stenosis in newborns 1, 2
• Metronidazole is suggested as safe for breastfeeding patients 4, 1, 2
• Rifampin can be used with an approach similar to other patient populations 4, 1, 2

Antibiotics Requiring Caution

Two antibiotics require specific limitations during breastfeeding:

• Clindamycin should be used with caution as it may increase the risk of GI side effects in the infant, including diarrhea, candidiasis, or rarely antibiotic-associated colitis 4, 1, 2, 5
• The FDA drug label confirms clindamycin appears in breast milk at concentrations of 0.5 to 3.8 mcg/mL and states that while breastfeeding need not be discontinued, an alternate drug may be preferred 5
• Doxycycline use should be limited to 3 weeks maximum without repeating courses, and only if no suitable alternative is available 4, 1, 2
• Short-term tetracycline use (3-4 weeks) is compatible with breastfeeding, but longer courses risk tooth discoloration and bone growth suppression in infants 2

Antibiotics to Avoid

Three antibiotic classes should not be used as first-line treatment:

• Fluoroquinolones (ciprofloxacin, levofloxacin) should not be first-line options, though if absolutely necessary, ciprofloxacin is preferred due to lower breast milk concentrations 1, 2
• Aminoglycosides should not be used during breastfeeding due to potential risks to the infant 1
• Co-trimoxazole should be avoided in premature infants, jaundiced babies, or those with G6PD deficiency 2

Essential Monitoring Considerations

All breastfed infants whose mothers take antibiotics require monitoring:

• Monitor for gastrointestinal effects (diarrhea, gastroenteritis) due to alteration of intestinal flora 2, 3, 5
• Watch for changes in stool pattern or consistency 3
• Be aware that antibiotics in breast milk could potentially cause falsely negative cultures if the infant develops fever requiring evaluation 2, 3
• Monitor for candidiasis (thrush, diaper rash) or rarely blood in stool indicating possible antibiotic-associated colitis 5

Clinical Decision Algorithm

Follow this hierarchy when selecting antibiotics for breastfeeding patients:

1. First choice: Amoxicillin or amoxicillin/clavulanic acid 1, 2, 3
2. Alternative β-lactams: Cephalosporins (cephalexin, ceftriaxone) 1, 2
3. For penicillin allergy: Erythromycin or azithromycin (avoid azithromycin in first 13 days postpartum) 1, 2
4. Use lowest effective dose for shortest necessary duration to minimize infant exposure while maintaining therapeutic efficacy 3

Important Caveats

Breastfeeding should not be interrupted when using recommended antibiotics:

• The benefits of continued breastfeeding outweigh the minimal risks of antibiotic exposure through breast milk 2
• The small amounts of antibiotic in breast milk are not therapeutic for the infant—if the baby develops an infection, they require their own appropriate dosing 2
• Most antibiotics in clinical use are considered suitable during breastfeeding when pharmacokinetic profiles are properly considered 6, 7, 8