Red Burning Rash On Side Neck, Flared Up, Reoccurring. Permanent Treatment?

The morning of thanksgiving, I noticed a slight red burning rash at the left side of the base of my neck . I put some lotion on it. It got a lot better. A few days later it flared up and went mostly all the way around my neck, started creeping up my neck. A bit on my face, eyes swoll & wrinkled. It subsided when I got some cortizone and put on it. I thought it was better, but it keeps coming back. I have tried to figure it out by process of elimination. Had recently started rogaine. Stopped. Stopped using bath shower gel. Stopped using athletic supplements . We lived in this apartment for 6 months prior to this happening, yet the worst part of the flare up always seems to come about when I m home. I m at a complete loss.