I have had cholinergic urticaria for over a half a year now (i break out with hives all over my body after a warm shower or pe class). this is very very very frustrating and i wish to know what drug i should buy to stop it, how long does it take to go away, when i should stop taking it.

i read that claritin may help...does it stop the hives from coming, or is this bs?

please give me some answers now cause it's very embarassing changing in pe with 40 red marks all over the body that itch like hell :(