I have a rash on the top of my hand, over where my fingers meet my hand (3rd, 4th and pinky). It s an active rash that has little blisters and sometimes bleeds. It s extremely itchy and it i put baking soda on it, it explodes but eventually takes the itch away and dries up. It has spread to a part of my 4th finger which usually sits on the mouse. I work on the computer all day. I ve never had this before but the last 2 years i ve had my hand on top of a mouse every day, all day. The palm of my hand is unaffected. When I use a mouse it feels like it starts to itch.