I Have Itchy Chest,neck And Arms,i Never Get Sweat. Is This Normal ?

This started as soon as I turned 13, I am now 18 going on 19 and I still have the same problem. I m an Asian Male, I have seen my family practitioner about this however I have not received a clear answer and he prescribed a anti- histamine which had no effect. My chest , neck, arms and scalp would become itchy as soon as my body suddenly got warm ( eating warm soup or stepping into a sauna) It s at its worse during the wintertime and still taunts me during the summer. My only remedy is drinking an excessive amount of water compared to my friends, (2-3 glasses of water during every meal ) and if I miss my quota, A few days later, my problems return. Do make note that I cannot sweat, even when doing something athletic (I get problems there too) I do think it s dehydration and my body cannot remove toxins easily, but I d like the comfort of confirmation.