Heat Rash?

[MarkyP05]

after exercise of any kind, or in fair hot conditions my chest goes all blotchy red, it doesnt itch or burn but is rather unsightly. I think it may be a heat rash of some kind but i was wondering if there is anyway to reduced the redness (which goes itself after a while) or stop it coming up?

[helliebobs]

anti-histamine cream works well afterwards as does taking anti-histamine tablets daily.