There's a vitamin that might just do the trick, and pronto. Niacinamide (be very careful that you get the -amide form of B3) is a natural antihistamine. It blocks a process called mast cell degranulation, the histamine-releasing process that can cause itching, hives, runny nose, etc. You can safely take 500 mg, up to four times a day. Works in 20 minutes (if histamine is the problem).

Lar