Recently, we blogged about a new meta-analysis that found an increased
risk of heart defects in infants born to women who use anti-depressants
known as SSRI's late in pregnancy. In fact, some anti-depressants
can cause a range of birth defects if taken by women during pregnancy,
though the risks aren't necessarily reflected by the classification
by the Food and Drug Administration (FDA).
Office on Women's Health in the U.S. Department of Health and Human Services estimates 13 percent
of pregnant women and new mothers suffer from depression. This is significant
because these women often seek medical help for their feelings of hopelessness
and despair. That help often comes in the form of prescription drugs like
selective serotonin reuptake inhibitors, or SSRIs.
These anti-depressants carry risks specific to pregnant women and their
unborn children. Though they are all part of the same drug class, SSRIs
are not all classified the same and do carry risks of birth defects.
SSRI Risks Vary By Drug
Danish study published in the British Medical Journal found the use of Zoloft and Celexa
early in pregnancy slightly increased the risk of a heart defect in infants.
The same association was not seen in other SSRIs, including Prozac and Paxil.
The most recent
meta-analysis, for instance, found a "statistically significant" association
between pulmonary hypertension in newborns and SSRI usage late in pregnancy.
In 2005, the
Food and Drug Administration found the risks associated with Paxil to be so significant that they changed
the classification of the drug as to fetal risk. Two separate studies
at that time found that women taking Paxil during the first trimester
to be one-and-a-half to two times more likely to deliver a baby with a
heart defect compared to women not on antidepressants or even those on
The FDA changed Paxil from a pregnancy category C drug to a pregnancy category
D drug. These categories guide doctors as to which drugs carry risks of
birth defects and may prescribed for pregnant women. In fact, drugs in
either pregnancy category C and category D can cause birth defect. There
is just more evidence of human fetal risk of birth defects based on patient
experience or human studies in category D drugs.
Drugs in either category C or category D may be prescribed to pregnant
women if the benefits outweigh the risks.
Category X drugs, at the far end of the spectrum, are those that should
never be prescribed to pregnant women.
The problem with Paxil's label change is that it came late-after pregnant
women had already taken the drug and given birth to children with birth
defects. They didn't receive the proper warnings. Drug makers have
a legal responsibility to make and market drugs that are safe when used
as directed and to provide adequate warning of known dangers.
After Paxil was reclassified as a category D drug, doctors would look for
an alternative category C SSRI drug to prescribe to patients who were pregnant.
Different Drugs = Different Risks
Zoloft, Paxil, Prozac, and Celexa are all SSRIs. They regulate the uptake
of serotonin, a neurotransmitter. But, they don't all have the same
formulations or effects. So, while they may be in the same class of drugs,
they are very different.
Drug makers should know the risks of their products and should share that
information with doctors and patients. Doctors then are able to help patients
choose the right prescription regimen given their symptoms and the risks
and benefits of the many drug choices. When any breakdown in this line
of communication occurs, it's the patient and her unborn baby who
stand to suffer.
Dangerous drugs are the responsibility of the manufacturers that develop and market them.
Ultimately, the patients stand to lose the most when the risks are not
made abundantly clear.