It sounds as though it may be hives, which come and go the way you describe. Despite their allergic reputation, the vast majority of hives are not allergic--they come for no reason and go away the same way. While you're waiting to see a doctor, you can use an over-the-counter anti-itch lotion containing camphor, menthol, or pramoxine. As for HIV, I see no reason for you to worry about that. If the rash is still there after the weekend, let a doctor check it out.
Best.
Dr. Rockoff
Thanks for your reply doc, i logged in under a different name but its still me malibuaz1234. Anyways i have no intentions or plans on seeing a dcotor or anything and i dont need any itching creams or anything because it never itch only when it was just starting to come in and plus its not even there anymore. By the time i wrote the original question to you it was already gone. It pretty much looked like an average diaper rash. I was wondering what it was and what caused it.
In the last 4-6 weeks I keep getting this rash on and off on both of my arms. It's a red and lumpy rash. Looks like mosquito bites. It itches a little then goes away after an hour or more. Then a day or 2 later it comes back. Just wondering what this might be? Possibly hives or some sort of an allergic reaction? Any help you could give would help thanks.