Hello, Welcome to health care magic. The possibilities of the rash include flexural eczema and contact allergy to deosprays/ perfumes. You could use a mild topical steroid like fluticasone or mometasone twice a day for about 10-15 days till the itching stops followed by regular use of moisturizer. If you have started using a new deodorant/ perfume, please discontinue it. Hope this helps you. Take care.