From the Guidelines
Amoxicillin is not considered teratogenic and is classified as a Category B medication, meaning it can be safely used during pregnancy when necessary, as supported by the most recent evidence from 2020 1. The use of amoxicillin during pregnancy has been extensively studied, and the majority of the evidence suggests that it does not pose a significant risk to the fetus. According to the European Respiratory Journal study from 2020 1, amoxicillin is listed as a Category B medication, indicating that animal studies have not shown risk to the fetus, and there are no adequate studies in pregnant women showing harm. Some key points to consider when prescribing amoxicillin during pregnancy include:
- The typical adult dose is 250-500 mg every 8 hours or 500-875 mg every 12 hours, depending on the severity of the infection.
- Treatment duration usually ranges from 7 to 14 days.
- As with any medication during pregnancy, the potential benefits should outweigh any potential risks.
- The safety of amoxicillin in pregnancy is attributed to its mechanism of action, which targets bacterial cell wall synthesis, a process not present in human cells, including those of the developing fetus. It's essential to note that while amoxicillin is considered safe, there is a concern that exposure to this antibiotic during organogenesis may be associated with oral clefts, although the risk is very low 1. Additionally, amoxicillin+clavulanic acid is not recommended in women at risk of pre-term delivery due to a very low risk of necrotising enterocolitis in the fetus 1. However, these risks do not outweigh the benefits of using amoxicillin when necessary to treat bacterial infections during pregnancy.
From the FDA Drug Label
Teratogenic Effects: Reproduction studies have been performed in mice and rats at doses up to 2000 mg/kg (3 and 6 times the 3 g human dose, based on body surface area). There was no evidence of harm to the fetus due to amoxicillin. There are, however, no adequate and well-controlled studies in pregnant women Because animal reproduction studies are not always predictive of human response, amoxicillin should be used during pregnancy only if clearly needed.
Amoxicillin Teratogenicity:
- The available animal reproduction studies show no evidence of harm to the fetus due to amoxicillin.
- However, there are no adequate and well-controlled studies in pregnant women.
- Therefore, amoxicillin should be used during pregnancy only if clearly needed 2, 2.
From the Research
Amoxicillin Teratogenicity
- Amoxicillin is a penicillin antibiotic, and according to 3, penicillins are a first-line antibiotic treatment during pregnancy, except in cases of maternal allergy to penicillin.
- A study published in 4 found no increased risk of adverse pregnancy outcomes, including congenital malformations, associated with amoxicillin exposure during pregnancy.
- The study in 4 compared pregnancy outcomes between women who had been prescribed amoxicillin during pregnancy and those who had not, and found that the adjusted mean birth weight of children born to amoxicillin-exposed mothers was actually higher than that of children born to controls.
- Another study 5 lists beta-lactams, which include penicillins like amoxicillin, as generally considered safe and effective in pregnancy.
Safety Considerations
- As stated in 6, when prescribing antibiotics during pregnancy, consideration must be given to both maternal and fetal well-being, and therapy should be directed toward the maternal disease while being safe for the fetus.
- According to 7, the choice of antibiotic during pregnancy requires consideration of the effects on both the mother and the unborn child, and some antimicrobial agents are safe for use throughout pregnancy, while others are completely contraindicated.
- The study in 3 notes that while the vast majority of antibiotics do not cause serious harm to the unborn child if used properly and at the appropriate doses during pregnancy, no medicine, including antibiotics, can be described as absolutely safe.