BackgroundSarcoptes scabieiis a permanent obligate ectoparasite that lives and reproduces in the epidermis of humans and other mammals worldwide. There is a lack of information on the molting process ofSarcoptes scabiei. Ivermectin is widely used to treatSarcoptesinfection in humans and animals, while the survival of moltingSarcoptesmites in the presence of ivermectin is unknown. The aim of the present study is to investigate the molting process ofSarcoptesmites and assess the activity of ivermectin during the molting process ofSarcoptesmites.Methodology/Principal findingsmoltingSarcoptesmites were incubated at 35°C and 80% relative humidity and observed hourly until complete molt. Of the 192 molting mites recorded, the longest molt periods for larvae and nymphs were 23 and 30 h, respectively. The activity of ivermectin on moltingSarcoptesmites was also assessed using two concentrations of the drug (0.1 and 0.05 mg/ml). The exposure time for molting mites was determined by 100% mortality of female mites exposed to the solution of ivermectin. While all female mites were killed after exposure to 0.1 mg/ml ivermectin for 2 h and and 0.05 mg/ml for 7 h, 32% and 36% of molting mites survived and successfully molted, respectively.Conclusions/significanceThe present study demonstrated that moltingSarcoptesmites are less susceptible to ivermectin than active mites. As a consequence, mites may survive after two doses of ivermectin given 7 days apart due not only to hatching eggs but also to the resistance of mites during their molting process. Our results provide insight into the optimal therapeutic regimens for scabies and highlight the need for further research on the molting process ofSarcoptesmites.