I had horrible acne from age 12 to age 32. What cured it was isotretinoin, which was marketed under the brand name accutane. (It is now generic.) It is a nasty medicine, with lots of side effects, but it really is a miracle drug for acne.
If you are a woman, you MUST be using birth control if you are to take isotretinoin because it produces horrible birth defects in a fetus. That even applies if you are not married and not sexually active in any way, because of the possibility chas v’shalom that you might be sexually assaulted.
The story of isotretinoin is interesting: It was discovered by the 1940s that large doses of Vitamin A would cure acne. My mother took Vitamin A supplements as a teenager for HER acne. The problem is that for most people, if you take enough Vitamin A to cure your acne, you destroy your liver in the process. You do not want to trade acne for a liver transplant. So the chemists came up with a synthetic slightly modified Vitamin A that wasn’t as toxic, and that chemical is isotretinoin. It is also used in some cancer treatments as a chemotherapy agent because it kills rapidly dividing cells — the same characteristic that produces such horrible fetal birth defects.
Consult Your Local Dermatologist, and good luck!