Can you tell me what could do for an itchy rash on foot?

I would recommend: You see a foot doc or dermatologist since we can't see the rash....

Rash: Although it sounds simple , rashes are anything but simple . See your podiatrist for assistance as we cannot see your rash .

Hydrocortisone cream: You can try this first. If worsens or feels to resolve, see Podiatrist or Dermatologist.

Foot rash: This rash would likely need to be examined and more history obtained to be able to provide you with useful input about the diagnosis or possible treatment.