Ivermectin is an anti-parasitic medication commonly used in animals to combat lice, fleas, and other parasites, but is it safe to use on humans? Yes and no. Ivermectin has been prescribed as a treatment for river blindness (onchocerciasis) since 1981, and it’s now used globally by the World Health Organization to prevent this disease in those at risk of contracting it. However, giving ivermectin to humans isn’t completely without risk, and there are other treatments that can be prescribed in its place Ivermectin for Humans.