In the study on mice clobetasol teratogenicity was revealed its fetotoxicity when administered subcutaneously maximum dose – 1 mg / kg, when administered at doses of mg / kg was found clobetasol teratogenicity. These dosages comprise about 33% and 1%, respectively, of the recommended dose topical ointment clobetasol for human use. The observed malformations: the cleaved skull, cleft palate, and other developmental disorders of the skeleton. Just set teratogenic activity when administered to laboratory animals relatively low dose. It is also found that certain glucocorticoids have teratogenic activity when applied to the skin of laboratory animals. The local use of teratogenic activity of clobetasol has not been studied. However, given the ability of clobetasol absorption through the skin in vivo were conducted with subcutaneous administration of the drug. In these studies found expressed clobetasol teratogenicity in mice rabbits. The drugs have a higher clobetasol teratogenic potential than drugs glucocorticoids with less activity. The duration of the carcinogenicity study of clobetasol has not been carried out. Clobetasol cream propionate mutagenic activity have been identified in the Ames test, using the accounting method of gene conversion in yeast species Saccharomyces cerevisiae. In studies on rats administered 50 mg / kg per day clobetasol. It showed a reduction in the number of viable fetuses, increased cases of resorption of embryos.