Taking zolpidem in pregnancy is generally considered safe when necessary to treat insomnia, but pregnant patients are often urged to try other options first. This is because this drug has been ranked in Pregnancy Category C by the U.S. Food and Drug Administration (FDA). This is likely because animal studies performed on zolpidem in pregnancy have shown some adverse side effects, though there are no properly controlled studies on humans that can say for sure whether it is safe. In general, doctors only tend to prescribe this drug for pregnant patients when insomnia is severe enough to have a negative effect, at which point the benefits may outweigh the risks.
Animal studies that have been performed with this drug have shown some adverse effects for the fetus, though the animals were often given much higher doses than pregnant women would normally get. For example, some test subjects that were given high doses of zolpidem in pregnancy had fetuses that displayed incomplete skull ossification. In addition, the rate of miscarriage and stunted growth of the fetus got higher as the dose of zolpidem was increased. In many cases, though, normal doses of zolpidem in pregnancy have not been shown to have a negative effect on the fetus or mother.
There have been some minor studies performed on women who took zolpidem in pregnancy and, while they were not necessarily controlled properly, their results show there is some risk in taking this drug. For example, some women who took the drug during the third trimester reported severe respiratory depression in their newborn baby, but this can typically be treated while at the hospital so the effects are not long-term. An additional worry about zolpidem in pregnancy is the possibility that babies will be born addicted to the drug. Newborn zolpidem addiction is often characterized at birth by withdrawal symptoms that may include sweating, vomiting and muscle pain. Finally, some newborn babies seem limp and weak at birth when they have been exposed to zolpidem in the womb.
Mothers who wish to avoid these possible effects are encouraged to find alternatives to taking zolpidem in pregnancy and should only take this drug when their insomnia is extreme and nothing else works to treat it. In most cases, the insomnia should disappear after pregnancy; if it does not, then this drug may be prescribed without incident. Breastfeeding mothers, however, should adhere to the same precautions as pregnant women when taking this drug, because it does show up in breast milk, and the effect on nursing babies is unknown.