Nitro-Bid and Pregnancy
In animal studies on the active ingredient in Nitro-Bid (nitroglycerin ointment) and pregnancy, the drug did not cause any problems. However, because animals do not always respond to medicines in the same way as humans, a pregnant woman should only use this drug if the benefits to her outweigh any possible risks to the unborn child.
Can Pregnant Women Use Nitro-Bid?Nitro-Bid® (nitroglycerin ointment) is a prescription skin ointment approved for the prevention of chest pain (angina). It is also used "off-label" for the treatment of anal fissures (a different nitroglycerin ointment, Rectiv™, is approved for anal fissure treatment). Based on information currently available, it is unclear if the drug is safe for use during pregnancy.
What Is Pregnancy Category C?Nitro-Bid is classified as a pregnancy Category C drug. 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 adequately studied in pregnant humans but have caused fetal harm 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.
When given to pregnant rabbits, nitroglycerin, the active ingredient in Nitro-Bid, did not cause any problems. However, it cannot be assumed that the same is true for humans, as animals do not always respond to medicines in the same way that humans do.
Therefore, a pregnancy Category C medicine, including Nitro-Bid, should only be given to a pregnant woman if her healthcare provider believes that the benefits to her outweigh any possible risks to her unborn child.
Other forms of nitroglycerin have been used to control high blood pressure during pregnancy and have also been used to help stop preterm labor by relaxing the uterus. It is unknown whether Nitro-Bid would be safe or effective for these uses.