The Basics
What is Penicillin G?
Penicillin used to treat and prevent certain infections caused by bacteria.
Brand names for Penicillin G
Penicillin G Potassium
How Penicillin G is classified
Anti-Infective Agents, Antibacterial Agents, Penicillins
Penicillin G During Pregnancy
Penicillin G pregnancy category
Category BNote that the FDA has deprecated the use of pregnancy categories, so for some medications, this information isn’t available. We still think it’s useful to list historical info, however, given what a common proxy this has been in the past.
What we know about taking Penicillin G while pregnant
Reproduction studies performed in the mouse, rat and rabbit have revealed no evidence of impaired fertility or harm to the fetus due to penicillin G. Human experience with the penicillins during pregnancy has not shown any positive evidence of adverse effects on the fetus. There are, however, no adequate and well controlled studies in pregnant women showing conclusively that harmful effects of these drugs on the fetus can be excluded. Because animal reproduction studies are not always predictive of human response, this drug should be used during pregnancy only if clearly needed.
Taking Penicillin G While Breastfeeding
What are recommendations for lactation if you're taking Penicillin G?
Limited information indicates that penicillin G produces low levels in milk that are not expected to cause adverse effects in breastfed infants. Occasionally disruption of the infant’s gastrointestinal flora, resulting in diarrhea or thrush have been reported with penicillins, but these effects have not been adequately evaluated. Penicillin G is acceptable in nursing mothers.
Maternal / infant drug levels
Limited information indicates that penicillin G produces low levels in milk that are not expected to cause adverse effects in breastfed infants. Occasionally disruption of the infant’s gastrointestinal flora, resulting in diarrhea or thrush have been reported with penicillins, but these effects have not been adequately evaluated. Penicillin G is acceptable in nursing mothers.
Possible effects of Penicillin G on milk supply
Relevant published information was not found as of the revision date.
Possible alternatives to Penicillin G
List of References
Lactation sources: Drugs and Lactation Database (LactMed) [Internet]. Bethesda (MD): National Library of Medicine (US); 2006-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK501922/1. Greene HJ, Burkhart B, Hobby GL. Excretion of penicillin in human milk following parturition. Am J Obstet Gynecol. 1946;51:732-3. PMID: 21025164
2. Rozansky R, Brzezinsky A. The excretion of penicillin in human milk. J Lab Clin Med. 1949;34:497-500.
3. Borderon E, Soutoul JH et al. [Excretion of antibiotics in human milk]. Med Mal Infec. 1975;5:373-6.
4. Matsuda S. Transfer of antibiotics into maternal milk. Biol Res Pregnancy. 1984;5:57-60. PMID: 6743732
5. Rollier R, Rollier M, Bellouchi M. [Herxheimer’s reaction in maternal milk in early congenital syphilis.] Bull Soc Fr Dermatol Syphiligr 1967;74:178-80. PMID: 6070262
Disclaimer: This material is provided for educational purposes only and is not intended for medical advice, diagnosis, or treatment. Consult your healthcare provider with any questions.
