@voiletj,
Did you mean shingles instead of scabies? The is a prescription medication that is swallowed rather than rubbed in. It's expensive, but sometimes works.
For skin rashes, I pre hydrocortisone cream which in non prescription up to 1% concentration. I have no idea if it would work on shingles, but if I had the disease again, I would give it a try.
Sorry, no herbal suggestions.