What are the causes of a rash and hives all over the body without any itch?

Hives usually itch: If you have a rash that resembles hives but doesn't itch, it probably isn't hives. Hives almost always itch and therefore is probably another type of rash. Unfortunately, rashes are usually diagnosed by physical examination and the history, so it will be difficult to help you over the internet and you likely will need to be examined by a physician.