Not sure this is the answer to the rash but.....

I went thru 8 years of an autoimmune disease that caused hives from top to bottom. I spent 4 years on a steroid which had horrific side effects.

I spent hours researching and found a drug called Xolair that I was able to use and get off of the prednisone.

But during the prednisone time, it didn't always work quickly and I started using something called super cold aerosol spray. VERY CAREFULLY SPRAY IT ON THE ITCHY PART OF THE AREA AS IT DOES FREEZE THE SKIN. I sprayed it sparingly and let it dry and it eliminated the rash by actually freezing the skin.

You will get a scab where it froze the skin but the cause of the rash was eliminated.

I did this several times over the 4 years on Prednisone. I never had to do it again during the 4 years on Xolair.

Then about 2 weeks ago I had another attack of itchy rash on my foot. I suspect it was from shedding.

I used my can of super cold spray (on Amazon) - sprayed it once a day for 3 days and put antibiotic cream on it. The rash disappeared. The scab appeared (and it itches but only because it is healing) and I continue to put antibiotic cream on it.

It is clearing up but I will never be without the freezing spray! NEVER!