Hello, I have been having this reoccurring rash on my neck, it comes and goes roughly once a month for a week, then it gradually recedes. This covers the entire circumference of my neck. The rashes get very itchy at night especially & they sting when I sweat. I?ve tested negative for HIV, Hepatitis A, B,C, chlamydia & syphilis. It?s been an ongoing problem for about a year now and I?ve used hydrocortisone, canesten, but they all seem to not be working. Please, I could use some sort of pre diagnosis before I visit my local MD. Thanks.