"i thought this medication wouldn&#039;t be that effective but i was wrong. it cleared my skin in 5 days and even got rid of large cystic acne that i had for like 6 months and nothing helped! i am amazed. everyone is saying how my skin is glowing and beautiful. well i didn&#039;t really think it was the doxycycline doing it until i stopped and bam broke out all over again. so i started back on it and in 2 days it is clearing the large cystic acne that came back. the only down side is it gives me stomach cramps and pain. i think it helps to drink a lot of water. if you are skeptical of this just give it a try. it works well for adult hormonal acne."