I haven't posted in quite some time, but have been reading posts. My son has suffered with acne since he was 14 and is now 20. You name it, prescription and non-prescription, 3 dermatologists, accutane, every product imaginable - he has tried it. High dosage of vitamin A and 50 mg. zinc worked for a while pretty good, then started breaking out again. This is the 3rd month he has been taking a probiotic recommended by a pharmacist, and he is clearer now than ever before. She advised the first 2 weeks, there would be some improvement, and that it might take 6 months of probiotics -- but he is almost completely clear on month 3. It is wonderful! His is severe cystic acne, and he does have some scarring -- that he can deal with later. I think I'll ask the pharmacist about the scarring too, because she truly has helped more than any derm. Hope this info helps someone else too.