acne
"I started taking Doxycyline this week, and already my skin seems to be getting better. I'm 20, and recently developed bad acne on my back, as well as a mild case on my face. After five days, my skin is clearer. I haven't had any of the nausea people have mentioned, although I occasionally get cramps if I haven't eaten. I have noticed that I'm getting sunburnt easier, but that's nothing a good dose of sunblock can't remedy."