Pregnancy and the Eye Part 3

Pregnancy drug classes, established by the FDA, categorize medications based on their potential risks to the fetus when taken during pregnancy. Class A drugs have been tested in pregnant women and found to be safe, showing no risk to the fetus in the first trimester and no evidence of risk in later trimesters. Class B drugs have not been tested in pregnant women, but animal studies have shown no risk to the fetus, or animal studies have shown a risk that was not confirmed in human studies. Class C drugs are those where animal studies have shown adverse effects on the fetus, but there are no well-controlled studies in humans. The potential benefits of Class C drugs may warrant their use in pregnant women despite potential risks.

Class D drugs have evidence of human fetal risk based on adverse reaction data from investigational or marketing experience, but the potential benefits from the use of the drug in pregnant women may be acceptable despite the potential risks. Class D category often applies to drugs that are necessary to treat life-threatening conditions. Class X drugs have studies in animals or humans that demonstrate fetal abnormalities, and the risk of using the drug in pregnant women clearly outweighs any potential benefit.