Red and raised rash

Dear Ask The Doctor: Hi, I have a large rash on my waist, thighs, hips, back, chest (a little on my neck) and all over my arms. It started a few hours after I went to the beach, small red bumps on my hips, after two days the rash spread all over my body. It's itchy sometimes like when it get's too hot and sometimes it's itchy for no reason at all. I've tried my eczema cream, a cream that kills scabies and a cream for heat rash. But nothing works. This has been going on for a week and nothing has changed. Help!

Dear Karen: The rash you are experiencing may be due to cercarial dermatitis also known as a swimmer's itch. This is caused by an allergic reaction to bacteria and parasites in the water. The symptoms include development of small reddish pimples that are associated with itching and burning sensation. Pimples may develop into small blisters. Itching may last up to a week or more, but will gradually go away. Do not scratch the bumps as it may lead to bacterial infection. In most cases the symptoms are relieved by corticosteroid cream, calamine lotion or any over the counter anti-itch lotion.