Doxycycline
"This has worked very well for my acne, nothing I have tried in 3 years has worked this well. However, I am an athlete and I'm out in the sun everyday and if this same thing applies to you, do not take this. It makes you very sensitive to the sun and you will be in so much pain, especially in your hands. If you start taking this and feel sensitive to hot and cold, and notice your hands turning red then stop using this immediately because it only gets worse."