Ceftriaxone Safety in Pregnancy
Ceftriaxone is generally safe to use during pregnancy for most bacterial infections, with reproductive studies showing no evidence of embryotoxicity, fetotoxicity, or teratogenicity, though it should be used only when clearly needed as there are no adequate well-controlled studies in pregnant women. 1
FDA Classification and Safety Data
The FDA label indicates that reproductive studies in mice and rats at doses up to 20 times the usual human dose showed no evidence of harm to the fetus, and primate studies at approximately 3 times the human dose demonstrated no embryotoxicity or teratogenicity 1
However, because animal studies are not always predictive of human response, ceftriaxone should be used during pregnancy only if clearly needed 1
Ceftriaxone is excreted in low concentrations in human milk, requiring caution when administered to nursing mothers 1
Clinical Applications During Pregnancy
Ceftriaxone is effective and well-tolerated for treating various infections during pregnancy, including:
Gonorrhea: Intramuscular ceftriaxone 125 mg demonstrated 95% efficacy (41/43 cases) for treating gonococcal infection in pregnancy, with no significant adverse effects 2
Perinatal infections: In 8 cases of perinatal infections (including amniotic fluid infection, intrauterine infection, and pyelonephritis), ceftriaxone 2-4 g daily achieved a 75% efficacy rate with no adverse reactions observed in mothers or neonates 3
Pyelonephritis and chorioamnionitis: Ceftriaxone 2 g once daily showed excellent tolerance with complete remission in all cases without premature delivery 4
Pharmacokinetic Considerations
Pharmacokinetic parameters during the third trimester are similar to those in healthy non-pregnant subjects, requiring no dosage adjustment 4
No drug accumulation occurs during treatment, and residual concentrations at 24 hours remain above MICs for susceptible organisms 4
Important Limitation: Syphilis Treatment
A critical caveat exists for syphilis treatment:
The CDC states that data are insufficient to recommend ceftriaxone for treatment of maternal syphilis infection and prevention of congenital syphilis 5
Penicillin remains the only proven effective treatment for preventing maternal-to-fetal transmission and treating fetal syphilis infection 5
Pregnant women with penicillin allergy should undergo desensitization and receive penicillin rather than ceftriaxone 5
While one small study (n=11) suggested ceftriaxone 250 mg daily for 7-10 days may be effective for early syphilis in pregnancy 6, this contradicts current CDC guidance that prioritizes penicillin desensitization 5
Cross-Reactivity Risk
There is potential for cross-reactivity in patients with penicillin allergy, though the risk is generally low 5
For neurosyphilis in HIV-infected pregnant patients, some specialists suggest ceftriaxone 1-2 g IV daily for 10-14 days, but this remains based on limited observational data 5
Practical Recommendations
For bacterial infections other than syphilis: Ceftriaxone can be used safely at standard doses (1-2 g daily) when clearly indicated 1, 4
For gonorrhea: Use ceftriaxone 125-250 mg intramuscularly as a single dose 7, 2
For syphilis: Do not use ceftriaxone as first-line therapy; pursue penicillin desensitization instead 5