OT Allergic reaction question

How long does it take for an allergic reaction rash to go away? I have a rash that spread all over my back to my chest and neck. I'm taking prednisone once a day, and I'm on my third day. My doctor said she would put me on a low dose.

Oh no, Katie!
Is it a reaction to meds or more like from dyes or perfumes in clothes?

My kids have sensitive skin and got rashes from laundry detergent, but after a Benadryl / Clairitin combo they were fine in a few hours.
I took anti-biotics once, had a reaction that included hives, and it took maybe 3 or 4 days to go away.

Hope you get some relief soon!!

I'm pretty much allergic to everything. I find its usually within 24 hours after I stop taking what's giving me the reaction. 

If you eliminate the allergen then it's pretty fast, less than a day.

That's hard to say, then. I have no clue what caused it. I haven't changed anything. 

You may not have changed anything, but a formulation might have changed. For example, a friend of mine is allergic to some substances, and her previously-fine laundry detergent made her break out since the company had changed the ingredients/formulation.

Sorry to be Debbie Downer, but it could be awhile unless you can pinpoint the cause.