I've never had a problem with acne. about 3 months ago i got what seemed like a rash all over my back and it hasnt gone away. it doesnt itch.

See doctor: It would be unusual to develop acne suddenly on your back at age 33. If you recently had a hormonal change such as starting or stopping birth control pills, it is possible. I would see your doctor to get the correct diagnosis and then appropriate treatment.

Acne on back?: if you have an acne rash on you back for the first time, it could be cased but Omer sweating during exercise without showering right away.. If this rash is not like acne and does not itch, it could be Pityriasis Rosea. Especially if it started with a similar lesion a few weeks earlier that was much larger. If this lesions are oval to round, slightly raised with a fine silver scale.

Rash: Without a picture it is not possible to accurately diagnose the rash; however, it is unlikely to be ACNE based on your history and description. Why are you on Bactrim (sulfamethoxazole and trimethoprim)? It also appears that you have other problems such as nausea and anorexia. It may be dermatitis if it is localized and may respond to systemic anti-histamine or topical steroid. It should be checked by a dermatologist.