As teenagers, my brothers and I suffered from severe acne. Nothing seemed to help. One day, quite by accident, I discovered kelp tablets. These are a health supplement, not a drug. Don't be afraid to use a high dosage. Available in a few pharmacies in Thailand, and online. I still use them at age 65, though taking a much reduced dosage. I pay somewhere around B 700 - 800 for a bottle that lasts me about 6 mo. For severe cases, you might have to spend that monthly, at least in the beginning.