Erythromycin and Pregnancy
Because the Food and Drug Administration considers erythromycin a pregnancy Category B drug, most healthcare providers consider it safe for women to take when expecting. Studies on pregnant animals did not indicate that erythromycin would cause problems. However, humans and animals can respond to medications in different ways, so it is best to check with your healthcare provider before taking any drug.
Erythromycin is a prescription antibiotic used to treat (and sometimes prevent) a wide variety of infections. Studies in animals and limited human data suggest that it is probably safe for pregnant women to take erythromycin, although the full risks are not currently known.
What Is Pregnancy Category B?
The U.S. Food and Drug Administration (FDA) uses a category system to classify the possible risks to a fetus when a specific medicine is taken during pregnancy. Pregnancy Category B is given to medicines that have not been adequately studied in pregnant humans but do not appear to cause harm to the fetus in animal studies.
Medications that have been shown to be safe for use in pregnancy in humans but have caused problems in laboratory animals are also given a Category B rating.
In general, most pregnancy Category B drugs are considered safe for pregnant women. For instance, acetaminophen (Tylenol®), the preferred painkiller during pregnancy, is a pregnancy Category B medicine.
Studies of pregnant rats who were given erythromycin did not suggest that the drug increases the risk of birth defects, miscarriages, or other problems for the fetus.
However, it is important to note that animals do not always respond to medicines the same way that humans do. Therefore, a pregnancy Category B medicine should be given to a pregnant woman only if the healthcare provider believes that the benefits to the woman outweigh any possible risks to the unborn child.
In most cases, the benefits of erythromycin (especially when treating serious infections) clearly outweigh the possible risks. Survey-type studies suggest that erythromycin is not linked to any problems during pregnancy.