I am in the 39th year of getting itchy arms. It always starts late spring in the right arm first, and at the shoulder first, working itself down the arm until the entire arm itches. This occurs about every 3-4 hours, and lasts about 45 minutes. Strangely, there seems to be hair growth during this time. It is only slight, but normally I have none. I have tried ice packs(seems to help the most) vinegar, soda, creams, hydrocortisone lotions. The bad part is it in the past goes to the left arm before it runs it's course.