I have a sever rash under my arms, my arpits are raw and feel as if on fire. What could be the cause of this and how do I make it go away?

Skin Infection. This is very common and it is also very common for both underarms to become involved. It usually starts off as a yeast infection but turns into a bacterial skin infection secondarily. One must stop deodorant and anti-persperant during the infection and most likely will need prescription medications to get this healed.