Best thing for harvest mites

[oofadoofa]

My horse is suffering at the moment with harvest mites, on his legs but also all round his face. I remember the vet telling me that Frontline flea spray was really good for getting rid of them, but wouldn't have thought this is safe to use on his face. It there anything else that works well?

 

[saz5083]

What about the Frontline spot-on stuff? Or put the spray on a cloth first and just wipe over?