itchy hands and feet at night

I just viewed some of the posts concerning itchy hands and feet at night. I have these symptoms and since I am a lab tech, have tested many times for lupus-all tests neg-even though I have roseacea on my neck. I am borderline diabetic-my Hgb A1c hovers around 5.9 and my dad and sisters and mother all have or had diabetes-his sisters starting in their forties and my dad at around 65. I am 54 and I do smoke and I'm a bit overweight. I am in menopause and seem to blame all my ills on that! I have had problems with one of my arms becoming extremely sensitive to any touch and once that arm starts to itch, it can go on for days. I have seen allergists and dermatologists, the latter prescribing atarax when needed and topical ointments. The only thing that seems to work is antihistamines, usually zyrtec. I also have mild dermatographia- I can't draw pictures on my skin with a stylus or pen like I have seen some people with it be able to do, but if I sleep with my arm and hand under my pillow or wear a watch or bracelets that put pressure on my skin, or carry a plastic shopping bag on my arm for even a few minutes, I get extremely itchy and break out in hives or small white spots on my arms or hands. When I am tired at night and sitting at the computer, my feet will start to burn and itch for no reason, and then my hands start, expecially under my wedding rings. If the itch is due to something like diabetes, then wouldn't I itch elsewhere on my body? And why is it relieved by antihistamines if it isn't an allergic response to something? I am allergic to dust, pollen, some grasses and trees and have a mild egg allergy (about a 2 on the scales used for RAST testing which is considered a mild allergy). I also have a mild cat allergy and we do have 2 cats, but I was like this even during a 4 or 5 year period when we didn't have pets. This has all seemed to escalate since I have gone through menopause, too.Now the skin on my affected arm has become rough and wrinkled as compared to the other arm. I'm beginning to think I should be tested again for scleroderma too. Do you think this is a good idea? Again, if this isn't a histamine reaction of some kind, due to diabetes or lupus like diseases, then why is it somewhat relieved with antihistamines?