Paroxetine linked with increased risk of birth defects when taken in early pregnancy

Using paroxetine - a drug prescribed to treat conditions including depression, obsessive-compulsive disorder, anxiety and posttraumatic stress disorder - during the first trimester of pregnancy may increase newborns’ risk of congenital malformations and cardiac malformations.

That’s the conclusion of a recent analysis published in the British Journal of Clinical Pharmacology. Paroxetine is the active ingredient of GlaxoSmithKline’s once blockbuster but now off-patent Paxil/Seroxat.

Up to one-fifth of women of childbearing age experience depressive symptoms that often lead to mild to moderate depression, and prescriptions for antidepressants during pregnancy have increased in recent years. The most common drugs for treating depression in pregnant women are selective serotonin reuptake inhibitors, and up until 2005, one drug in that class – paroxetine - was considered to be safe for use during pregnancy. A small unpublished study conducted by the manufacturer, however, suggested an increased risk of cardiac malformations in infants exposed to paroxetine before birth. Subsequent studies using various study designs in different populations across Europe and North America generated conflicting results in terms of statistical significance, although a trend remained towards an increased risk.