Ivomec does not repel or keep ticks from attaching to dogs. There are no properties in Ivomec that work against ticks, nor fleas for that matter. Years and years, myself and others around me have given Ivomec once a month as a heartworm preventative, but it does not repel or kill fleas and ticks, that I know for sure. I've heard a couple folks here and there that are under that misconception, but it is indeed a falsehood.
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