Ceftriaxone Safety in Pregnancy
Ceftriaxone is generally safe to use during pregnancy, with FDA classification showing no evidence of teratogenicity in animal studies, though it should only be used when clearly needed as adequate human studies are limited. 1
FDA Classification and Safety Data
- The FDA label states that reproductive studies in mice and rats at doses up to 20 times the usual human dose showed no evidence of embryotoxicity, fetotoxicity, or teratogenicity 1
- Primate studies at approximately 3 times the human dose demonstrated no embryotoxicity or teratogenicity 1
- However, the FDA emphasizes that animal studies are not always predictive of human response, so ceftriaxone should be used during pregnancy only if clearly needed 1
- Ceftriaxone is excreted in low concentrations in human milk, requiring caution in nursing mothers 1
Clinical Efficacy Data in Pregnancy
Ceftriaxone has demonstrated effectiveness for specific infections during pregnancy:
- A study of 8 perinatal infections treated with 2-4g daily IV ceftriaxone for 2-10 days showed 75% efficacy (6/8 cases), with no adverse reactions observed in mothers or neonates 2
- For gonorrhea in pregnancy, ceftriaxone 125mg IM achieved 95% efficacy (41/43 cases) with no significant adverse effects 3
- Pharmacokinetic studies in pregnant women during the third trimester showed similar parameters to non-pregnant adults, with no drug accumulation and excellent tolerance 4
Important Limitations for Syphilis Treatment
For syphilis in pregnancy, ceftriaxone is NOT recommended as a substitute for penicillin:
- CDC guidelines explicitly state that "data are insufficient to recommend ceftriaxone for treatment of maternal infection and prevention of congenital syphilis" 5
- Penicillin remains the only proven effective treatment for preventing maternal transmission to the fetus and treating fetal syphilis infection 5
- Pregnant women with penicillin allergy should undergo desensitization and receive penicillin rather than alternative agents 5
- One small study (n=11) suggested potential efficacy of ceftriaxone 250mg IM daily for 7-10 days in early syphilis during pregnancy, but this is insufficient evidence for routine recommendation 6
Approved Indications in Pregnancy
Ceftriaxone is appropriate for:
- Gonorrhea: 125-250mg IM as recommended by CDC 7, 3
- Chancroid caused by Haemophilus ducreyi: 250mg IM 7
- Various bacterial infections during the perinatal period when clearly indicated 2, 4
Key Clinical Caveats
- Cross-reactivity with penicillin allergy exists, though the risk is generally low 5
- For neurosyphilis in HIV-infected pregnant patients, some specialists suggest ceftriaxone 1-2g IV daily for 10-14 days, but this remains based on limited observational data 5
- The devastating effects of untreated syphilis in pregnancy far outweigh concerns about penicillin desensitization 7
- Ceftriaxone should not be used in hyperbilirubinemic neonates as it can displace bilirubin from serum albumin 1