I responded earlier from my cell phone, but feel I need to encourage you again to look at diet. Do you consume cow milk products? Try omitting dairy for at least a month.Someone mentioned probiotics. I always tend to forget/neglect that, but it's a great idea.
Topical ointments and treatments can provide relief and quicken the clearing of the symptoms, but you want to find out the cause.
Since your problem is so localized, this may not apply, but for my family, I stopped using fabric softeners as a solution to bumpy and itchy skin. We don't need them, and they only add chemicals to our clothing (much is then inhaled or absorbed through the skin) and to our water systems. On that same contact-type issue, I once developed a problem on my neck and chin that I tracked down to a scarf I had begun wearing in the fall. It had animal hair in it, and for some reason that was causing my skin to flare up.
Whether it is contact-related or dietary, if possible try to find out the cause so you won't have to keep treating the symptoms. Take care and I hope you figure it out. - Bird