Concerns have been raised over a possible link between an anti-nausea drug and the risk of serious birth defects. This is of particular concern, since anti-nausea drugs like Zofran may be prescribed to pregnant women suffering from morning sickness.

Zofran (ondansetron) is a powerful anti-nausea drug. In the United States, it is approved to treat nausea from chemotherapy, radiation therapy, and anesthesia. However, physicians are allowed to prescribe drugs like Zofran above and beyond their approved purposes. However, physicians may risk birth defect side effects when prescribing drugs like Zofran to patients for other purposes.

According to The Toronto Star, about 20 women who were prescribed Zofran during pregnancy suffered serious birth defects, including heart defects and kidney defects. Some of the reports even included infant deaths in mothers who took Zofran during pregnancy. While this was not a peer-reviewed study, The Toronto Star noted that these reports are troubling.

A potential parallel played out in the 1960s. During this time, before tighter regulations by the U.S. Food and Drug Administration (FDA), a drug called thalidomide was prescribed to treat morning sickness during pregnancy. Like Zofran, thalidomide was experimental and not fully approved to treat morning sickness. Thalidomide interferes with the development of blood vessels.

When given to a pregnant women, thalidomide prevents the formation of new blood vessels, which causes a cascade of changes to a developing fetus. This can produce a child with serious birth defects, including hands growing directly out of the shoulder. Since then, the FDA and similar agencies have instituted tight protocols for testing drugs like Zofran to evaluate the risk of birth defects. Unfortunately, off-label usage for Zofran could circumvent these precautions.

Under federal law, a physician may prescribe a drug like Zofran “off-label.” In the United States, the FDA requires strict testing for safety and efficacy before a drug maker can promote and distribute a drug like Zofran.

However, physicians are allowed to prescribe drugs for other purposes. This can be useful in cases where research moves faster than FDA approval for desperate patients. However, off-label usage can also mean that physicians are flying blind in uncharted territory.

In the case of Zofran, there are relatively few studies on the safety of the drug with respect to pregnancy. Though Zofran is only approved to treat serious nausea from chemotherapy, radiation treatments, and anesthesia, Zofran is widely prescribed to treat morning sickness.

In the past, birth defect lawsuits have been filed against drug companies who produce drugs linked to birth defects. Such birth defect lawsuits typically allege that drug makers did not do enough to protect the public against the risk of birth defects allegedly linked to drugs like Zofran.