I have used Ivermectin for years on cattle. The pour on version, absorbs thru the skin. Inadvertently dosed myself at times too.
That reminds me of an old joke...
...Cattle Rancher tells his friend that the vet
gave him a new aphrodisiac to give to his bull.
...Friend asks what he thought of it.
...Rancher says “it tasted kinda like like peppermint.”