Have you heard of accutane treatment? It is very expensive and there are several precautions, but perhaps you have insurance that covers it as we were blessed to have. My son, a college student had the worst acne case that I have seen after he started his first year of college. There are several precautions and he had to have blood work done also on each visit to the dermatologist who monitored him closely. He had these treatments about two years, I think a bit longer than most people, but today he looks great and one would never know how bad he once looked. Erythromicin prescriptions didn't work for him either. Ask your dermatologist about it. If he is reluctant, I would advise getting a second opinion. We did it as a last resort and have no regrets so far. He has been off the medication for about a year and is now a handsome young man.