With deer populations as high as they are around here they will get used to most spray products because hunger overrules deterrents. They have stripped forests of the under story plants except for barberry. With no saplings surviving, these forests will not last for more than 50 years.
There is a company that specializes in deer deterrent, can't think of there name at the moment. Fencing is the only long term solution I know of.
If you're trying to reduce ticks, don't bother spraying lawns because tick habitat is shady, brush and tall grasses.
The nation that destroys its soil destroys itself.
Franklin D. Roosevelt