Oral antibiotics that should be used or avoided during pregnancy

Many commonly used antibiotics are safe. But some should be avoided, and many have special precautions. Penicillins, cephalosporins, and clindamycin..
Abdelwahab Ward, BS Pharm, PharmD

Which oral antibiotics are okay during pregnancy? ― Many commonly used antibiotics are safe. But some should be avoided, and many have special precautions.

  • Penicillins, cephalosporins, and clindamycin are generally safe.
  • Metronidazole (Flagyl). Labeling discourages its use in pregnancy due to concerns about fetal malformations. But explain that short courses, such as for bacterial vaginosis or trichomoniasis, are okay. Problems haven't shown up in the thousands of pregnant women who have used short courses.
  • Quinolones should be avoided, they are linked to cartilage damage in young animals.
  • Tetracyclines should usually be avoided, they are linked to tooth staining and adverse bone effects in children exposed during pregnancy.
    • But explain that doxycycline doesn't seem to be associated with these adverse effects.
    • So, a short course of doxycycline may be okay when there aren't good alternatives.. such as for Rocky Mountain spotted fever.
  • Macrolides are a mixed bag. Point out that azithromycin (Zithromax) or erythromycin (Erythrocin, Erythrin) is safe if a macrolide is needed. But don't recommend clarithromycin as animal studies suggest it's linked to birth defects.
  • TMP/SMX (Septrin DS) is okay in the second trimester. But caution that trimethsulfonamides in the last 2 months of pregnancy, they may cause dangerously high bilirubeels ioprim in the first trimester is linked to birth defects.. since it's a folic acid antagonist. And avoid in lvn the infant.
  • Nitrofurantoin (Macrofuran, Uvamin Retard) is often okay, but advise avoiding it during the last month of pregnancy due to rare cases of hemolytic anemia in newborns.
  • Get our notes, "Antibiotics use in pregnancy" to know the safety of antibiotics during pregnancy. Also read the simple notes, "Notes on using antibiotics while breastfeeding" and "Put macrolide use during pregnancy in perspective".

References

  1. Briggs GG, Freeman RK. Drugs in Pregnancy and Lactation. 10th edition.
  2. Anon, (2019). Bacterial Vaginosis - 2015 STD Treatment Guidelines. [online] Available at: https://www.cdc.gov/std/tg2015/bv.html.
  3. ACOG Committee Opinion No. 494: Sulfonamides, nitrofurantoin, and risk of birth defects. Obstet Gynecol. 2011;117(6):1484-1485.
Abdelwahab Ward, BS Pharm, PharmD