How long does it take for eczema to go away if I use hydro cortisone cream 1 percent and the eczema is on part of my back, part of the arms, neck, face?

Hydrocortisone 1% Although most versions of hydrocortisone 1% cream or ointment are labeled as maximum strength, this only means maximum strength to be sold without a prescription. Pharmacologically, hydrocortisone is a weak corticosteroid when compared to others in the same class. There are many, corticosteroid creams that are much more potent, but require a prescription. I sugges a visit to a dermatologist.
Be sure eczema. If what you have is eczema and it is the extent you say it is, you will need a prescription strength medication to deal with it. The distribution of the eruption as you describe it is somewhat atypical for eczema . You should see a dermatologist and get a definitive diagnosis and treatment for your condition. Treated properly, the eruption should clear within a few days.
ECZEMA. THERE ARE DOZENS OF DIFFERENT ECZEMAS. IF YOU HAD IT AS A CHILD, IT IS CALLED ATOPIC DERMATITIS. OR ATOPIC ECZEMA. IF YOU DIDNT HAVE IT AS A CHILD, IT COULD BE SOMETHING FROM THE OUTSIDE THAT YOU MIGHT BE ALLERGIC TO. WHERE IS THE RASH LOCATED? DO SEE YOUR PCP, AND IF THE PCP CANNOT MAKE THE DIAGNOSIS, HE OR SHE MIGHT REFER TO A DERMATOLOGIST.. THANK YOU FOR YOUR QUESTION.