Baclofen and Pregnancy
Animal studies on baclofen (Lioresal, Gablofen) and pregnancy have shown that this medication may increase the risk of a certain birth defect in the wall of the stomach. Although this is a pregnancy Category C medication, a healthcare provider may still prescribe it if the benefits to the woman outweigh the possible risks to the unborn child.
Is Baclofen Safe During Pregnancy?Baclofen (Lioresal®, Gablofen®) is a prescription medication used to treat spasticity due to various causes, such as multiple sclerosis (MS) or spinal cord injuries. Little information is available about the potential risks of using baclofen when pregnant.
Baclofen and Pregnancy Category CThe U.S. Food and Drug Administration (FDA) uses a category system to classify the possible risks to a fetus when a specific medicine is taken during pregnancy. Pregnancy Category C is given to medicines that have not been studied in pregnant humans but that do appear to cause harm to the fetus in animal studies. Also, medicines that have not been studied in any pregnant women or animals are automatically given a pregnancy Category C rating.
When given to rats, baclofen increased the risk of omphalocele (a defect in the abdominal wall that allows a section of the intestines to protrude) and incomplete bone hardening. In mice, decreased fetal weight and delayed bone hardening were reported.
However, it is important to note that animals do not always respond to medicines in the same way that humans do. Therefore, a pregnancy Category C medicine may be given to a pregnant woman if the healthcare provider believes that the benefits to the woman outweigh any possible risks to the unborn child.
Only a few cases of baclofen use in pregnancy have been reported. In most cases, the women were receiving the drug via a pump (to deliver the medication directly to the spinal cord). No problems were reported. It should be noted that with this method of administration, blood levels of baclofen are approximately 100 times less than the levels that occur with oral use of the medication. Therefore, oral use may be more likely to cause problems.