Natroba and Pregnancy
Natroba (spinosad) has not been studied in women who are expecting. However, if used as directed, it is generally safe during pregnancy. The active ingredient in Natroba is not absorbed through the skin to any significant extent, so it is not expected to reach the baby in amounts large enough to cause problems.
Natroba® (spinosad) is a prescription head lice medication. Based on the results of animal studies, this medication does not appear to pose a significant risk to the fetus.
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 B is given to medicines that have not been adequately studied in pregnant humans but do not appear to cause harm to the fetus in animal studies.
Medications that have been shown to be safe for use in pregnancy in humans but have caused problems in laboratory animals are also given a Category B rating.
Natroba has not been studied in pregnant women. However, the active ingredient (spinosad) is not absorbed through the skin to any significant extent, and would therefore not reach the baby in any significant amount.
Animal studies did show some problems when very high doses were given by mouth to pregnant animals. However, the dosages were high enough to cause toxicity in the mother animals, and the problems are probably the result of the maternal toxicity, not of a direct effect on the baby animals. Such problems are extremely unlikely to happen with Natroba.
However, it is important to note that animals do not always respond to medicines the same way that humans do. Therefore, a pregnancy Category B medicine should be given to a pregnant woman only if the healthcare provider believes that the benefits to the woman outweigh any possible risks to the unborn child.
It should be noted that benzyl alcohol (one of the inactive ingredients in Natroba) can cause dangerous problems in newborns and is generally not recommended for use in pregnant women. No studies have been done to see how much benzyl alcohol is absorbed into the bloodstream with Natroba.