"i developed cystic acne, i&#039;m guessing as a result of hormones, stress, and genetics. my doctor and i changed what we were using during the second visit, since we were doing some trial and error (figuring out what works). since my skin is not sensitive, we went from a combination of doxycycline, tretinoin, and clyndimicine (idk how to spell it) to a combination of tretinoin of higher strength, erythromycin/bp gel, and minocycline. my skin has cleared up in a matter of 2 months with the occasional pimples and some acne scarring. i had to switch from doxy to mono because after my first round of doxy, my insurence would not cover any form of it for some reason, i which is why i gave it a 5."