What antibiotics are safe during breastfeeding (lactation)?

From the Guidelines

Most antibiotics are safe to use during breastfeeding, but the safety depends on the specific medication, with generally safe options including penicillins, cephalosporins, and macrolides like azithromycin, as noted in the most recent study 1.

Safe Antibiotic Options

• Penicillins (amoxicillin, ampicillin) are considered safe for use during breastfeeding, as they pass into breast milk in very small amounts, typically less than 1% of the maternal dose, which is generally too low to cause problems in the nursing infant 1.
• Cephalosporins (cefdinir, cefuroxime) are also safe, with human data indicating that cefuroxime and other cephalosporins are not teratogenic at usual therapeutic doses 1.
• Macrolides like azithromycin are generally safe, although an epidemiological study suggests a very low risk of hypertrophic pyloric stenosis in infants exposed to macrolides during the first 13 days of breastfeeding 1.

Antibiotics to Avoid or Use with Caution

• Tetracyclines (doxycycline) are usually safe for short courses under 3 weeks, but may be associated with tooth discoloration and transient suppression of bone growth in the infant 1.
• Ciprofloxacin should be avoided during pregnancy and lactation due to potential fetal cartilage damage, although human data suggest a low risk 1.
• Metronidazole can be used during pregnancy and lactation if there are no other safer alternatives, but may cause taste changes in milk and should be used with caution 1.
• Sulfonamides should be avoided in infants under 2 months or premature babies due to the risk of hyperbilirubinemia and fetal hemolytic anemia 1.

Monitoring and Precautions

• When taking antibiotics while breastfeeding, watch for potential side effects in the baby, such as diarrhea, thrush (oral yeast infection), or rash.
• Taking probiotics during and after antibiotic treatment may help prevent digestive issues for both mother and baby.
• Always inform the healthcare provider that you are breastfeeding when antibiotics are prescribed so they can select the safest option for your specific situation.

From the FDA Drug Label

Nursing Mothers 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 Monitor the breast-fed infant for possible adverse effects on the gastrointestinal flora, such as diarrhea, candidiasis (thrush, diaper rash) or rarely, blood in the stool indicating possible antibiotic-associated colitis

• Clindamycin is considered relatively safe during breastfeeding, but it may cause adverse effects on the infant's gastrointestinal flora.
• The decision to use clindamycin during lactation should be based on the mother's clinical need and the potential risks to the infant.
• Monitoring the breast-fed infant for possible adverse effects is recommended 2.

From the Research

Antibiotics Safe During Breastfeeding

• Penicillins, aminopenicillins, clavulanic acid, cephalosporins, macrolides, and metronidazole are considered safe for use during breastfeeding, as stated in 3 and 4
• Fluoroquinolones can be used during breastfeeding, but should not be the first-line treatment, according to 3
• The use of antibiotics with short half-lives, such as Cefotaxime and Ceftriaxone, minimizes the risk of accumulation in breast milk, as mentioned in 5

Antibiotic Groups and Infant Exposure

• Cephalosporins are the most studied group of antibiotics, with 21 studies included in the review, as reported in 6
• The calculated infant exposure to antibiotics via breast milk varies between 13% for macrolides and 38% for broad-spectrum penicillin, as found in 6
• Metronidazole has the highest assessed exposure as a percentage of infant therapeutic dose, at 11%, according to 6

Antituberculosis Medications During Breastfeeding

• Most antituberculosis drugs, including isoniazid, rifampin, ethambutol, and streptomycin, appear to be safe for use during breastfeeding, as stated in 7
• The percentages of the therapeutic dose of antituberculosis agents that may be delivered to nursing infants range from 0.05% to 28%, as reported in 7
• It is recommended to examine the infant for signs and symptoms of toxicity if the mother chooses to breastfeed while taking antituberculosis medications, according to 7