CATEGORY (A¸B¸C¸D¸X¸DRUGS)

FDA pregnancy risk categories that indicate risk to a fetus from maternal use of a drug. Category A drugs have not shown a risk in controlled studies. Category B drugs either have not been tested in animals or show adverse effects in animals which have not been confirmed in humans. Category C means that no controlled studies have been done in humans. Category D indicates that there is evidence of human fetal risk, but the benefits of the drug may outweigh the risk. Category X includes drugs which in animal and human studies (or common experience) have been shown to cause fetal abnormalities.