Subutex and Pregnancy
When the active ingredient in Subutex (sublingual buprenorphine) was given to pregnant animals, it caused several problems in the offspring, including stillbirth, reduced offspring growth, and decreased litter size. If you happen to be taking Subutex and you become pregnant, your healthcare provider will weigh the risks and benefits before making a recommendation.
Subutex® (sublingual buprenorphine) is a prescription medication used to treat opioid dependence. This medication may not be safe for use during pregnancy, although the full risks are still unknown. However, it may be safer than continued use of other opioids, especially illegal ones, although methadone is usually the preferred drug in this situation.
Subutex 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.
Subutex has not been adequately studied in pregnant women. In studies with pregnant and lactating rats, high doses of buprenorphine, the active ingredient in Subutex, increased the risk for stillbirth, reduced offspring growth, and decreased litter size. It is important to note, however, that the doses used were high enough to cause toxicity in the mother rats.
It is known that buprenorphine passes through the placenta to the developing fetus. Thus, chronic use of buprenorphine during pregnancy may cause the baby to become dependent on the drug. Because the baby is no longer getting the medication (via the mother) after birth, narcotic withdrawal symptoms may occur. This will occur even if the mother breastfeeds, as the baby would receive less of the drug through breast milk than it received during pregnancy.
Symptoms of narcotic withdrawal in the newborn may include:
- Decreased respiration (decreased breathing)
- Changes in behavior, such as irritability, jitteriness, or restlessness
- Excessive or high-pitched crying
- Poor feeding
However, pregnancy Category C medicines, including Subutex, may be given to a pregnant woman if her healthcare provider believes that the benefits to her outweigh any possible risks to her unborn child. Although methadone is usually the preferred drug to treat opioid dependence during pregnancy, since there is more experience with using methadone in pregnant women, some early research suggests that Subutex might have a role for this use as well.