Suggest OTC Cream For Skin Rashes On Armpits

I have a rash on one of my armpits that comes and goes. It's itches, and seems to go away after a few days. I quit using deodorant, to see if it would help. That didn't help. I don't wear any tight clothes, nor do I wear any synthetic clothing. All my clothes are cotton. I've used the same soap. Is there any over the counter cream that I can use? I've been putting lotramin af on it. And I can't tell any difference. Any suggestions?