Tretinoin
"I had acne since 11 and I'm now 22, but Retin A really helped my get rid of them in 3 months. (I also cut dairy which is what I believe had caused my acne.) I started using retin A at 0.025->0.05% and I am seeing huge difference in my skin. Pores are significantly smaller as all my friends have complimented on how good my skin looks. Scars are going away faster than they do normally. I didn't have initial breakout like most people have. There's only occasional peeling when I don't drink enough water. I do notice my skin regenerate A LOT faster so remember to gently exfoliate your skin (light med peel). Amazing as it sounds, do give it a few months (or more depending on how your skin reacts to it). Going for 0.1% and I'll see how it goes!"