FDA: Long-Term Terbutaline Use Not Safe for Pregnant Women

Heidi Turner Washington, DC: It has been well over 10 years since the US Food and Drug Administration (FDA) issued a Dear Colleague letter, warning healthcare professionals about Terbutaline side effects. That letter warned about the risks of serious side effects associated with administering Terbutaline during pregnancy. Since that time, the FDA has received reports of women who died or who suffered serious cardiovascular events after receiving terbutaline for preterm labor, leading the FDA to issue a stronger warning about the use of terbutaline by pregnant women.

In February 2011, the FDA issued a warning against using terbutaline to treat preterm labor. Terbutaline is approved to prevent or treat narrowing of the airways associated with asthma, bronchitis and emphysema. It is not approved for use during preterm labor. In issuing its warning, the FDA noted that "the prolonged use of this drug to prevent recurrent preterm labor can result in maternal heart problems and death."

As a result, the FDA required the addition of a boxed warning and contraindication to the label of the terbutaline injection packages, warning against its use for prevention or prolonged treatment of preterm labor. The FDA notes that prolonged treatment is anything beyond 48 to 72 hours. In urgent situations, injectable terbutaline may be used if clinically appropriate, but the FDA warns that it should not be used over longer periods of time and should not be used in an outpatient or home setting.

Furthermore, the FDA warns that oral terbutaline should not be used at all for treatment or prevention of preterm labor because "it has not been shown to be effective and has similar safety concerns" to the injectable terbutaline.

According to the FDA, a search of the Adverse Event Reporting System (AERS), found 16 maternal deaths, reported from 1976 to 2009. Meanwhile, 12 cases of serious cardiovascular events in pregnant women were reported to AERS from January 1, 1998 through July 2009. Among the cardiovascular events were cardiac arrhythmias, myocardial infarction, pulmonary edema and tachycardia.

The FDA concluded that "the risk of serious adverse events outweighs any potential benefit to pregnant women receiving prolonged treatment with terbutaline injection (beyond 48–72 hours), or acute or prolonged treatment with oral terbutaline."

In a letter regarding a citizen petition, the FDA notes that terbutaline was moved from pregnancy risk category B to pregnancy risk category C.