Aldara and Pregnancy
The U.S. Food and Drug Administration has classified Aldara (imiquimod) as a pregnancy Category C medication, meaning it may not be safe for women who are expecting. During animal studies, high doses of the drug appeared to cause miscarriages, exencephaly, and delayed bone hardening. However, there may be cases where the benefits of using Aldara outweigh the potential risks to the fetus.
Aldara® (imiquimod cream) is a prescription medication used to treat actinic keratosis (a type of precancerous skin lesion), basal cell carcinoma (a type of skin cancer), and genital or perianal warts. It is unclear if this medication is safe for use during pregnancy, as the full risks are currently unknown.
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. Aldara is classified as a pregnancy Category C medication.
Pregnancy Category C is given to medicines that have not been studied in pregnant humans but do appear to cause fetal harm in animal studies. Also, medicines that have not been studied in any pregnant women or animals are automatically given a pregnancy Category C rating.
When given to pregnant animals at very high doses (by mouth or intravenously), imiquimod, the active ingredient in Aldara, caused a few different problems, such as:
- Increased miscarriages
- Low fetal weight
- Delayed bone hardening
- Bent limb bones
- Exencephaly, a problem where the brain develops outside of the skull
- Protruding tongues
- Low-set ears.
However, it is important to note that animals do not always respond to medicines in the same way that humans do. Therefore, a pregnancy Category C medicine may be given to a pregnant woman if her healthcare provider believes that the benefits to the woman outweigh any possible risks to her unborn child.
Keep in mind that with normal skin use (for the mother), the fetus would be exposed to a very, very small amount of the drug. In the few cases of fetal exposure to imiquimod (due to maternal use of the skin cream), no problems were seen. Also be aware that using more of the cream than recommended significantly increases the amount of the drug absorbed (more so than would be expected), potentially exposing the fetus to higher levels of the drug.