Rash That Comes and Goes?

I'm not really sure what's going on. Lately I have been noticing these blotches and/or spots on my skin. The weird part of this is though that they will disappear within an extremely short amount of time. They are usually gone within 15 minutes to and hour; at the most maybe an hour and a half. They don't at all. They actually don't have any feeling to them at all. They don't hurt, they have no irritation, nothing. Originally they were only appearing on my legs during my dance classes while I was stretching and would then go away. Now though they are beginning to appear in my arms just randomly throughout the day, mostly if there is pressure being applied to that area. I'm completely befuddled by what this could be. At first I thought that maybe I had heat rash, but when I looked at the symptoms, they didn't seem to match up. I would really like to avoid going to the doctor if possible. If anyone knows what this may be please tell me. I've been trying to do research on it but nothing that I can find ever seems to match up to my symptoms.

[Bhupinder Kaur, MD]

Hello,
These itchy red patches which appear suddenly can be due to hives or urticaria. Hives (medically known as urticaria) are red, itchy, raised areas of skin that appear in varying shapes and sizes and most of them are idiopathic.
Do not use any cosmetic products at the sites. You can apply some calamine lotion at the rash as it will help in soothing the skin. You can take some OTC oral antihistamine medications like Benadryl or Claritin and see if it helps.

For mild-moderate symptoms a weak steroid may be used, whilst more severe cases require a higher-potency steroid. But they are available under prescription and should be taken only after consulting a dermatologist. Also try to identify the allergens which you might be coming in contact with which may be causing the hives.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.