If you're going to try retin-a, perhaps consider getting a prescription for Tazorac which is more potent than retin-a and works quite a bit better in my opinion. I would try to alternate between using this and a glycolic acid every night to really tack the cysts.

Also, antibiotics are great short term, but in the long run they really aren't great for acne. I've been on every antibiotic for acne and was even on amoxicillin for over a year. These worked while I was on it until I became resistant or stopped taking it. Now I'm left with digestive problems which I don't think was worth it for short term effects.

I've been on the regimen for 8 months, except I use tazorac instead of Dans AHA and alternate between that and a glycolic acid every night as previously recommended. Having had severe acne since age 11, this is the only regimen that has every provided clearance for me. The only thing was that it took about two months to completely clear, but my acne was quite severe and I have horrible atrophic scarring to prove it.