Drugs in Pregnancy
According to the American Centers for Disease Control (CDC), about two-thirds of women in the U.S. take one or more prescription medications during pregnancy. However, most medications have not been adequately studied for their safety during pregnancy. Therefore, it is very important to pay attention to medications use in pregnancy, especially during the first trimester, which is a crucial time of development of fetal organs.
Before taking any prescription drug, OTC drug, or a herbal drug, a pregnant woman, or a woman planning to become pregnant should consult physician or pharmacist.
In order to indicate the potential of a drug to cause birth defects if used during pregnancy, the FDA has established the five categories system of drugs in pregnancy (namely, A, B, C, D, and X), with A category drugs being the safest to use in pregnancy, and X category drugs being contraindicated in pregnancy.
Drugs are assigned one of the following categories as follow:
A category: Studies in pregnant women show no risk.
B category: Animal studies show no risk, but human data are insufficient; or animal studies show toxicity, but human studies show no risk.
C category: Animal studies show toxicity, human data are insufficient, but clinical benefit may exceed risk.
D category: There is evidence of human risk, but clinical benefits may outweigh risk.
X category: There is evidence of fetal abnormalities in humans, and risk exceeds benefits.
Examples of drugs, known to be teratogenic, and should be avoided in pregnancy:
1. Danazol (X category)
2. Lithium (D category)
3. Phenytoin (D category)
4. Carbamazepine (D category)
5. Retinoids (X category)
6. Valproate (D category)
7. Warfarin (X category)
8. ACE inhibitors (D category)
9. NSAIDs (D category in 3rd trimester)
It is important for pregnant women to know that there is no drug that is 100% safe to be used in pregnant women. However, the following table shows examples of drugs that can be used in some of the commonly encountered situations for pregnant women after consulting their pharmacist or physician:
Condition to be treated
Recommended Drug
Heartburn
Antacids
Gas, upset stomach
Simethicone
Cough or cold
Guaifenesin, Dextromethorphan
Pain, Fever
Acetaminophen
Allergy
Chlorpheniramine, Loratadine
Itching
Topical Hydrocortisone
Nausea in early pregnancy
ginger root, vitamin B6
By:
Dr. Abdullah K. Rabba
Assistant Professor
Clinical pharmacy department
