Rash on back? or acne?

I have been having this random cluster of red acne like spots on the upper middle of my back. I'm not sure if it's acne or a rash from my laundry detergent? I've been using benzoyl peroxide acne cream but it's still there. It used to be raised a little like acne but now its all flat.  

[Dr Rajput]

Hi, welcome to the forum, the tiny spots on the skin other than acne, suggests atopic dermatitis which is seen due to allergic background and Contact dermatitis due to direct skin exposure to a substance which can be a allergen or irritant.

Anti-histamines with appropriate steroids against prescription will help to alleviate the condition. Identify and avoid the triggering factor which you been exposed to recently.

I suggest you to consult a dermatologist for further management. Take care and regards.

[Resilient_Mimi]

If it itches use benadryl to dry it up.  Otherwise use a good face cleaner and this should work for your back as well.