hello .thanks for your query..
I feel that you have something knows as Urticaria
.It is common condition with frequent exacerbations and remissions.In most cases,a direct cause is not identified.However a combination of correct anti histaminic tablets for a few months help in reducing the severity and frequency of these hives
You should not take bath in hot water.Sometimes urticaria can be reduced only by this.
Start application of a soothing anti pruritic calamine
lotion to relieve the itch.In certain cases, a few bood tests are advised to rule out ant internal causation of the same.
Do not worry,although symptoms and treatment course of urticaria is prolonged,these do not pose any danger in most people!
hope this helps!take care...