Amoxicillin and Breastfeeding
Amoxicillin is safe and compatible with breastfeeding, and nursing should not be interrupted when this antibiotic is prescribed. 1
Safety Classification and Evidence
Amoxicillin is explicitly classified as "compatible" with breastfeeding by the European Respiratory Society/Thoracic Society of Australia and New Zealand (ERS/TSANZ) guidelines and the American Academy of Dermatology. 2, 1 This represents the highest level of safety designation for antibiotics during lactation.
- The FDA classifies amoxicillin as Pregnancy Category B, and the drug label confirms that penicillins are excreted in human milk, though caution should be exercised. 2, 3
- Research confirms that penicillins and aminopenicillins, including amoxicillin, are present in breast milk at low concentrations. 1
- Multiple systematic reviews support that most antibiotics, including penicillins, are compatible with breastfeeding at recommended dosages. 4
Clinical Recommendations
The benefits of continued breastfeeding outweigh the minimal risks of amoxicillin exposure through breast milk, and breastfeeding should not be interrupted. 1
- Amoxicillin/clavulanic acid (Augmentin) is also considered safe and effective during breastfeeding, classified as FDA Category B and compatible with nursing. 2, 1, 5
- A prospective study of 67 women taking amoxicillin/clavulanic acid found that 22.3% of infants had minor adverse effects (primarily gastrointestinal), which were self-limiting and did not require interruption of breastfeeding. 6
- The rate of adverse effects increased with higher maternal dosages but remained clinically manageable. 6
Infant Monitoring
All breastfed infants whose mothers are taking antibiotics should be monitored for gastrointestinal effects, though serious adverse events are rare. 1
- Watch for mild diarrhea or gastroenteritis due to alteration of intestinal flora. 1
- Amoxicillin may lead to sensitization of infants, though this is uncommon. 3
- Antibiotics in breast milk could potentially cause falsely negative cultures if the breastfed infant develops fever requiring evaluation. 1
Important Caveat
When using amoxicillin/clavulanic acid specifically, exercise caution in women at risk of pre-term delivery due to a very low risk of necrotizing enterocolitis, but amoxicillin alone is considered safe. 1 This distinction is critical—plain amoxicillin does not carry this concern.
Dosing Considerations
- Standard adult dosing is 250 mg twice daily up to 500 mg three times daily. 2
- The lowest effective maternal dose should be used, and timing medication after breastfeeding can further reduce infant exposure. 7, 8
- Renal dosing adjustment is required in patients with severe renal impairment (GFR <30 mL/min). 3