The Safety of Prescription Drugs During Pregnancy

FDA Uses Five Pregnancy Risk Categories At Present

The FDA uses five risk categories to rank the safety of prescription drugs during pregnancy.  In recent years, the FDA pregnancy risk categories have gone from "A", the least problematic, to "X", the most dangerous.  The FDA is in the process of revising its pregnancy risk categories.  While waiting for the revisions, we wanted to provide an overview of the current pregnancy categories and show where some common prescription drugs are currently placed among those five risk categories.

Category A: Prescription drugs for which drug-safety studies did not indicate a risk during the first trimester of pregnancy and produced no evidence of risk in later stages of pregnancy. Very few popular prescription drugs fall into this category; thyroid medications are one example.

Category B: Prescription medications which, historically, have been used often during pregnancy and that do not seem to cause major birth defects or other problems. Examples: some antibiotics; famotidine (Pepcid); and, some types of insulin. Note: The corticosteroid nasal spray Rhinocort Aqua (budesonide) was moved into this class last year from Category C, where many allergy and asthma drugs reside.

Category C: Prescription drugs which, historically, have been more likely to cause complications for the mother or the baby.  This class also includes those drugs for which there is insufficient safety data. Examples: fluconazole (Diflucan); ciprofloxacin (Cipro); fexofenadine (Allegra); and, some antidepressants.

Category D: Prescription drugs which are known to impose health risks for the fetus. The placement of a drug into this class indicates that "positive evidence of human fetal risk exists, but the benefits from use in pregnant women may be acceptable despite the risk," according to an American College of Obstetricians and Gynecologists (ACOG) report. Examples: chemotherapy drugs and phenytoin (Dilantin).

Category X: Prescription drugs that have demonstrated a propensity to cause birth defects. The placement of a drug into this class indicates that "risk in pregnant women clearly outweighs any possible benefit," according to the ACOG report. Included in this most dangerous class are the acne drug Accutane as well as the psoriasis medications Tegison and Soriatane.

Medical experts stress that the risks of allowing health problems to go uncontrolled during pregnancy may outweigh the risks of the medications typically prescribed for them -- particularly for women with chronic medical conditions like asthma, diabetes, and high blood pressure.  This expert opinion assumes, significantly, that the prescribed drugs are taken under a doctor's supervision, and then only for the shortest time and at the lowest dose needed.  Accordingly, it is essential that women who are pregnant, or are planning to become pregnant, consult early on with those doctors who are currently prescribing drugs to them.

(Posted by: Tom Lamb)