Cephalexin
"I had perioral dermatitis, literally came out of nowhere, originally thought it was a pimple, then the next day just all around my mouth to the point where it hurt to talk, I left it for another day avoiding people, then the next day it got even worse, that is when I panicked. I could barely talk, eating was out of the question (thank God for Ensure and protein shakes). The doctor prescribed Keflex for me, 500mg, four times a day for ten days. It seriously worked wonders. Now I am back on this medication again for the same thing 8 months later, my doctor has no idea what causes it and apparently neither does Google. Anyways, I feel I can rest easy knowing I am on this product again and that it will be cleared up within the 10 days."