Antibiotics to Avoid During Pregnancy and Breastfeeding
Pregnancy: Antibiotics to Avoid
Tetracyclines (including doxycycline) must be avoided after the fifth week of pregnancy due to permanent tooth discoloration and enamel hypoplasia in the developing fetus. 1, 2
High-Risk Antibiotics - Contraindicated
Tetracyclines (doxycycline, tetracycline): Cause permanent yellow-gray-brown tooth discoloration during tooth development (last half of pregnancy through age 8 years), enamel hypoplasia, and decreased fibula growth rate in premature infants 1, 2
Aminoglycosides (gentamicin, tobramycin, streptomycin): Associated with eighth cranial nerve damage (ototoxicity) and theoretical nephrotoxicity in the fetus; streptomycin specifically linked to hearing damage 3, 2
Fluoroquinolones (ciprofloxacin, levofloxacin): Contraindicated as precautionary measure despite "unlikely" teratogenic risk, due to concerns about cartilage damage in developing joints 2, 4
Trimethoprim: Avoid especially during first trimester; use only short courses if absolutely necessary 3
Moderate-Risk Antibiotics - Avoid if Possible
Fluconazole: Doses ≥400 mg/day during first trimester associated with craniosynostosis and dysmorphic facies; doses >150 mg/day linked to miscarriage 3
Sulfonamides and cotrimoxazole: Second-line agents only; avoid in first trimester 3, 2
Vancomycin: Limited experience in first trimester; use only for life-threatening infections 3
Breastfeeding: Antibiotics to Avoid or Use with Caution
Fluoroquinolones should not be used as first-line treatment during breastfeeding due to theoretical cartilage damage concerns from animal studies, though ciprofloxacin is the preferred agent if this class is clinically necessary. 5
Antibiotics Requiring Caution
Fluoroquinolones (ciprofloxacin, levofloxacin): Not recommended as first-line due to cartilage damage concerns in animal studies; if indicated, ciprofloxacin is preferred within this class 5, 6
Chloramphenicol: Not considered compatible with breastfeeding due to toxicity concerns 4
Oral clindamycin: May increase risk of gastrointestinal side effects in the infant 7
Doxycycline: Limit use to maximum 3 weeks without repeating courses; use only if no suitable alternative available 7
Aminoglycosides (tobramycin, gentamicin): Avoid breastfeeding for 2 hours following IV injection when concentrations are maximal; monitor renal function and perform auditory testing if treatment prolonged 3
Macrolides (azithromycin, erythromycin): Very low risk of hypertrophic pyloric stenosis if used during first 13 days of breastfeeding; safe after 2 weeks 5, 7
Safe First-Line Alternatives
Penicillins (amoxicillin, ampicillin): Compatible with breastfeeding; considered low risk 3, 5, 8, 9
Cephalosporins (cefuroxime, ceftriaxone, cefadroxil): Compatible with breastfeeding; low oral bioavailability in infants 3, 5, 7
Amoxicillin/clavulanic acid: Safe and effective choice, FDA Category B 7
Metronidazole: Considered safe during breastfeeding 7
Critical Monitoring Considerations
All breastfed infants should be monitored for gastrointestinal effects (diarrhea, altered flora) when mother receives antibiotics 5, 7, 10
Antibiotics in breast milk may cause falsely negative cultures if febrile infant requires evaluation 5
Administer medication immediately following a breastfeed to minimize infant exposure, as peak milk concentrations typically occur 1-2 hours after oral dosing 10