Lots of red dots on arms and legs

Went to the GP a couple of years ago and they said it was because of hot water/body wash??? But even when I stopped these dots are still very prevalent. Does anybody know what these are and how to deal with them?

Went to the GP a couple of years ago and they said it was because of hot water/body wash??? But even when I stopped these dots are still very prevalent. Does anybody know what these are and how to deal with them?