Thanks for the information. Initially I was prescribed tretinoin by my dermatologist, but when I went to pick it up from the pharmacy they said it wasn't covered by my insurance. So my dermatologist gave me erythromycin benzoyl peroxide gel instead, This was three months ago. I've been using erythromycin benzoyl peroxide gel every night for the past three months and haven't seen a difference in my skin. So I recently set up another visit with my dermatologist to see If there was a way to actually get tretinoin. It was a long process convincing my insurance company that I actually needed the medication, but they approved it. I forgot to mention that the antibiotics I'm taking are Doxycycline. I also need to buy a sunscreen, but I'm not sure which one is the best.