Tizanidine and Pregnancy
In clinical studies on pregnant animals, tizanidine (Zanaflex) increased the risk of developmental delay and miscarriage. However, no studies have been performed on pregnant women using this product, so it is unclear if the same problems would occur. Your healthcare provider can provide information about the benefits and risks of using this medication in your particular situation.
Is Tizanidine Safe While Pregnant?Tizanidine hydrochloride (Zanaflex®) is a prescription muscle relaxant. Animal studies suggest that this medication could cause problems during pregnancy.
What Is Pregnancy Category C?
The 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 do appear to cause harm to the fetus in animal studies.
In addition, medicines that have not been studied in any pregnant women or animals are automatically given a pregnancy Category C rating.
Tizanidine has not been studied in pregnant humans. In pregnant animals, however, the drug can increase the risk of miscarriages, increase the length of pregnancy, decrease offspring survival (both before and after birth), and cause developmental delays.
However, it is important to note that animals do not always respond to medicines the same way that humans do. Therefore, a pregnancy Category C drug 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.