My mother is 83 and diagnosed with vascular dementia. She complains of itching at night, her legs mostly. It’s been going on for months. I have tried many thing and nothing works. Sometimes it's so bad that she's scratching till she starts bleeding. I’m up most of the night. I’m at my wits end.
In the end, what worked for my mother was the can of Dermoplast I bought her at Walgreens; it has a numbing agent in it when sprayed on the skin, deadens it for a little while giving her a chance to relax and forget about the itch. There are a few sprays like this available at the drugstore that give temporary relief from itching that comes from unknown origins. It's cheaper than trying 1000 different lotions and potions and still having your mother scratching herself bloody.
One day, mom said her 'rashes' disappeared and that was the end of the entire nightmare, thank God.
Best of luck.
First of all the skin of elders is terribly fragile. Make certain you are using anti-allergen soaps on laundry and no bleach. Check the bed in case bedbugs got in somehow; they can come from contact with any upholstered chairs anywhere. After you ruled all that out, discuss with MD as there are medications for this. Also for the creams that are without perfumes, and absorbed easily into skin to keep it from being too dry.
If this is coming from the dementia it will be more difficult. Check out any new medications recently added to list, as that can be a factor. Especially any pain meds.
Sorry you are going through this. You may want a dermatologist consult.
Just do know this isn't at all unusual. I hope you come to an answer.
It is very common, and sometimes there is no identifiable cause.
Good luck.
Another thing, when did the itching start? Was it soon after your Mom had gotten some new medicine. Sometimes it can be the filler, binder, or coating on a pill that some people find they cannot tolerate.
Or it could be the sheets on the bed. Any new detergent or softeners being used?