Feline Miliary Dermatitis ~ Pawprints and Purrs, Inc.
Sorry if I sounded patronising but I only asked that as my outside cat was like this and I didn't realise BobMartin flea products were rubbish at the time. I used Frontline and she is fine now.
I think I would take him to the vet. I am sure they could help out with something.
Hope he is better soon.