What could this be? a rash?

i have a rask on my back and about 3 inches below my armpit and it itches and my skin in bubbling what could it be?|||well it can be anything consult dermatologist.|||It's a rash and I know because my little cousin has what you described.|||Sweat rash, have you changed your deodorant?|||It might be rash but if it doesn't go away, it might be your skin problem. Go to the doctor if it gets worse.|||could be eczema. Have a doctor check it out.|||it might cause of heat.. always keep yourself cold no sweat... if still rash see doctor, get some lotion|||Probably eczema. Sometimes changing your laundry detergent or deodorant or body soap/wash can irritate the skin or cause an allergic reaction resulting in a rash/eczema or it could be a herpes infection if you've been letting someone kiss or nibble that spot.|||eczema? Atopic eczema.|||Although you are young it could be the shingles. Is the bubbling cracking, oozing, and scabbing over at all? See a dermatologist!