PAXIL FDA ALERT: Increased Risk of Neonatal Persistent Pulmonary Hypertension

[FDA July,2006] A recently published case-control study has shown that infants born to mothers who took selective serotonin reuptake inhibitors (SSRIs) after the 20th week of pregnancy were 6 times more likely to have persistent pulmonary hypertension (PPHN) than infants born to mothers who did not take antidepressants during pregnancy (see SSRI drug names at the bottom of this sheet). The background risk of a woman giving birth to an infant affected by PPHN in the general population is estimated to be about 1 to 2 infants per 1000 live births. Neonatal PPHN is associated with significant morbidity and mortality. The FDA is updating the prescribing information for all SSRIs with this new information. The FDA is also accruing data from additional sources pertaining to the potential association between SSRIs and neonatal PPHN. The FDA will provide additional information when it becomes available. In the interim, the FDA recommends that physicians carefully consider and discuss with patients the potential risks and benefits of SSRI treatment throughout pregnancy, including late pregnancy.

Decisions about how to treat depression in pregnant women are increasingly complex. Patients and physicians must carefully consider and discuss together the potential benefits and risks of treatment with antidepressants during pregnancy. Two new studies provide important information to be considered in making such decisions. The studies included women who had been treated with antidepressant drugs that act as selective serotonin reuptake inhibitors (SSRIs) or, in a few cases, other antidepressants. SSRI medications are the most commonly used drugs to treat depression in the U.S.

The first study illustrates the potential risk of relapsed depression after stopping antidepressant medication during pregnancy. The authors followed pregnant women who in the past had major depression. During their pregnancy, some of these women were not feeling depressed and stopped taking their antidepressant medicines. Others stayed on their antidepressant medicines while pregnant. The women who stopped their medicine were five times more likely to have a relapse of depression during their pregnancy than were the women who continued to take their antidepressant medicine while pregnant. This study, by Lee Cohen and other authors, was published February 1, 2006 in the Journal of the American Medical Association (JAMA).

A second study suggests there may be additional, though rare, risks of SSRI medications during pregnancy. This study focused on newborn babies with persistent pulmonary hypertension (PPHN), which is a serious and life-threatening lung condition that occurs soon after birth of the newborn. Babies with PPHN have high pressure in their lung blood vessels and are not able to get enough oxygen into their bloodstream. About 1 to 2 babies per 1000 babies born in the U.S. develop PPHN shortly after birth, and often they need intensive medical care. In this study PPHN was six times more common in babies whose mothers took an SSRI antidepressant after the 20th week of the pregnancy compared to babies whose mothers did not take an antidepressant. The study was too small to compare the risk in one drug compared to another, and this risk has not so far been investigated by other researchers. The study, by Christina Chambers and others, was published on February 9, 2006 in The New England Journal of Medicine.

The finding of PPHN in babies of mothers who used a SSRI antidepressant in the second half of pregnancy adds to concerns coming from previous reports that infants of mothers taking SSRIs late in pregnancy may experience difficulties such as irritability, difficulty feeding and in very rare cases, difficulty breathing. In addition, the labeling for paroxetine (Paxil) was recently changed to add information about findings in an epidemiology study suggesting that exposure to the drug in the first trimester of pregnancy may be associated with an increased risk of cardiac birth defects (see FDA Public Health Advisory for Paxil dated December 8, 2005).

The uncommon potential risk to the newborn of PPHN has not been confirmed by additional studies. Uncertainty about these rare events and their potential impact on the newborn, along with the potential risk to the mother of recurring depression if she stops her antidepressant medicines during pregnancy, makes decisions about the treatment of depression in pregnant women especially challenging for health care professionals and patients.

Women who are pregnant or thinking about becoming pregnant should not stop any antidepressant without first consulting their physician. The decision to continue medication or not should be made only after there has been careful consideration of the potential benefits and risks of the medication for each individual pregnant patient. If the decision is made to stop treatment with SSRIs before or during pregnancy, this should be done with a heart care professional, according to the prescribing information for the drug, and patients should be observed closely in case their depression comes back.

The FDA is seeking additional information about the possible risk of PPHN in newborn babies of mothers who took SSRI antidepressants in pregnancy. In the meantime, the FDA has asked the sponsors of all SSRIs to change prescribing information to describe the potential risk for PPHN.