Medications & Medication Safety
Many drugs are appropriate for use in pregnancy, if really needed. But a pregnant woman shouldn’t take any medication, even an over-the-counter one, unless she checks with her doctor first. If possible, she should avoid taking drugs in the first trimester or taking more than one medication at a time. She can also ask for the lowest dose possible to treat her condition.
Some medications have a long history of being used in pregnancy without problems. A pregnant woman shouldn’t be deprived of drug therapy she really needs, says Sandra Kweder, M.D., the co-chair of FDA’s task force on pregnancy labeling. She adds that women with pre-existing medical conditions such as epilepsy, lupus, asthma, or high blood pressure shouldn’t quit their drugs because of pregnancy. Safer drugs can be used if necessary, but those medical conditions still need to be treated.
Kweder explains, ‘A common thing with patients is that they’ll say, ‘I know I’m supposed to take medication, but I’m worried about my baby, so I’ll take less of it instead.’ They’ll take it every other day, or half as much. That’s not wise.’
The risks of a drug have to be weighed against its benefits. For example, some epilepsy drugs are known to cause birth defects, but an epileptic seizure can cause brain damageto the fetus. Most experts agree that the benefits of medication in such cases outweigh the risks.
Other drugs, however, are not so clear-cut. ‘It’s really hard because there aren’t easy answers,’ says Kweder. ‘For a baby to be healthy, it needs a mother who’s healthy.’ However, most drugs have not been tested scientifically in pregnant women. Reliable scientific information about medication use in pregnancy is often incomplete or non existent. FDA is trying to change that.
The agency has begun a comprehensive review about how it regulates drugs for pregnant women and how safety information is communicated on the label. The present system is not as helpful as the agency would like. ‘The system has been criticized, and rightly so,’ says Kweder. ‘It is complicated to interpret data for medications used in pregnancy. We’re making progress, but it’s slow.’
A new system is needed, she says, but it will be difficult to create. Drugs can’t be tested in pregnant women the same as in other groups of people. Animal studies, while helpful, don’t necessarily show what a drug will do to a woman and developing fetus.
In the meantime, a woman who has taken a drug and discovers she is pregnant should consult her doctor and avoid making decisions about her pregnancy in panic. While about 80 percent of approved drugs lack adequate scientific evidence about use in pregnancy, that doesn’t necessarily mean they can harm the fetus or are harmful in the doses prescribed.
Only a very few drugs definitely known to be extremely bad for a human fetus are clearly labeled or, in one case, have special requirements attached to their approval. The drug thalidomide, which was recently approved by FDA to treat leprosy and is being explored for other uses, is devastating to developing fetuses and causes severe deformities of the arms and legs. FDA is requiring that patients who take the drug enroll in a national registry that will track their progress monthly and record the occurrence of any pregnancy. The hope is that this process will discourage physicians from prescribing the drug to women who might become pregnant and keep patients from ‘sharing’ the drug with a woman of childbearing age.
here are times during your pregnancy when you may want or need to take medication. You may have a bad cold and want to take a decongestant to help you breathe, or you may develop a urinary tract infection (UTI) and need to take antibiotics for several days.
Before you begin taking any medication, you and your doctor need to discuss the benefits and possible risks of taking the medicine, as some medication has possible side effects that could harm your baby. To help doctors determine some of these benefits and risks, the U.S. Food and Drug Administration (FDA) has developed a labeling system for many common medications to easily express what is understood about using the medicine during pregnancy. These labels are used on prescription medications only; over-the-counter medications do not feature labels unless they were previously prescription-only medicines and were given a label at that time. The following chart shows the different letter categories and what they mean.
|Pregnancy Category||Definition||Examples of Drugs|
|A||In human studies, pregnant women used the medicine and their babies did not have any problems related to using the medicine.||• Folic Acid
• Levothyroxine (thyroid hormone medicine)
|B||In humans, there are no good studies. But in animal studies, pregnant animals received the medicine, and the babies did not show any problems related to the medicine.
In animal studies, pregnant animals received the medicine, and some babies had problems. But in human studies, pregnant women used the medicine and their babies did not have any problems related to using the medicine. • Some antibiotics like amoxicillin
|• Zofran® (ondansetron) for nausea
• Glucophage® (metformin) for diabetes
• Some insulins used to treat diabetes such as regular and NPH insulin
|C||In humans, there are no good studies. In animals, pregnant animals treated with the medicine had some babies with problems. However, sometimes the medicine may still help the human mothers and babies more than it might harm.
No animal studies have been done, and there are no good studies in pregnant women.
|• Diflucan® (fluconazole) for yeast infections
• Ventolin® (albuterol) for asthma
• Zoloft® (sertraline) and Prozac® (fluoxetine) for depression
|D||Studies in humans and other reports show that when pregnant women use the medicine, some babies are born with problems related to the medicine. However, in some serious situations, the medicine may still help the mother and the baby more than it might harm.||• Paxil® (paroxetine) for depression
• Lithium for bipolar disorder
• Dilantin® (phenytoin) for epileptic seizures
• Some cancer chemotherapy
|X||Studies or reports in humans or animals show that mothers using the medicine during pregnancy may have babies with problems related to the medicine.There are no situations where the medicine can help the mother or baby enough to make the risk of problems worth it.These medicines should never be used by pregnant women.||• Accutane® (isotretinoin) for cystic acne
• Thalomid® (thalidomide) for a type of skin disease
Information on many common medications can be found on the U.S. Food and Drug Administration’s website. The FDA is continuing to collect more information about the benefits and risks of taking specific medications during pregnancy.
You should always discuss with your doctor any medication you are taking or thinking of taking and be sure the prescribing doctor knows that you are pregnant. However, never stop taking any prescribed medication without talking with your doctor.