Doxycycline
acne
"Started seeing results after 48 hours.  One week into taking 100 mg once a day, my skin has cleared hugely.  The cystic bumps have stopped and my acne has reduced to the occasional white head, which sits on the surface instead of deep in the skin.  I'd recommend it, I wish I didn't take one year to get onto it.  I used it as a last resort as nothing topical worked."