Hi, I feel this cool sensation on the top of my head after I drink some water...sometimes I feel a little weird too along with it...like sort of out of it. I hardly feel thirsty, it doesn t matter what activity I m doing, I could go a day or two without drinking anything. I simply forget...I know I might have some dehydration issues, but why do I feel the cool sensation on my head after I do drink water? I also sometimes feel the same sensation in my back outer rib area, I guess where my kidneys are. Anyway, I appreciate any insight into what s going on...