Prevention is the best cure
The best combination I've found is Flowers of Sulfer and Permanon (Permethrin) spray.
Flowers of Sulfer is merely powdered sulfer. Our area is notorious for chiggers and ticks. I dump an ounce or two of sulfer into a sock that I keep in my truck. When I'm preparing to enter an area that it likely to be infested, I bang the sock onto my shoes, socks, and pantlegs to serve as a deterrant to the little boogers.
Permethrin is best used by spraying your clothes with it about 24 hrs before use. The treatment usually last for a couple of weeks, but this stuff works. It even kills ticks! I have used it by spraying it on my boots and pantlegs if I'm out in the field. With the sulfer and permethrin, I have been able avoid the itch! It's best not to let the permethrin get on your skin. The sulfer smells, well, like sulfer, but it works.