An in vivo evaluation of induction of abnormal sperm morphology by ivermectin MSD (Mectizan).

The in vivo effects of orally administered ivermectin (Mectizan) on sperm head morphology of albino mice were evaluated. Four different dose levels of 0.25, 0.5, 1.0 and 1.5 x the human therapeutic dose of 150 g kg(-1) body weight, were administered to the animals. The animals were exposed to a single oral treatment. The sperm of the mice from the cauda epididymes were examined 5 and 7 weeks after treatment. Ivermectin (Mectizan) induced sperm head abnormalities; however, the induction was not significantly elevated above the negative control value. Furthermore, the induction of the sperm head abnormalities was not strictly dose-dependent and there was also no correlation between dose level of administered drug and incidence of abnormal sperms. This indicates that the drug might not be mutagenic.