My Mother (92) sleeps from 10pm till sometimes 12:30 -1pm. Should I be worried?

Right. If she's just tired, then her sleeping may be okay. Maybe, she needs to rule out medical problems and then have someone available to help her with a good lunch or dinner, dental care and a couple of baths per week.

Janet, even if your Mom was conversing with you plainly and also sleeping a lot, remember she is in her 90's.... she is tired... she's had a very long life... and throw in a bunch of prescription medicines that say a side effect is drowsiness, of course she will sleep a lot.

As Sandwich and Sunny mentioned above, have your Mom see her primary doctor for a check-up. I would do that sooner than later.

There could be many reasons your mom is sleeping so much. I'd try to get her to a doctor to see what's going on. Maybe she's depressed or maybe she has dementia. Sometimes your body clock gets adjusted and it's difficult to get it to a different schedule.

What I would be concerned about too is to make sure she's getting her nutrition, dental hygiene, baths, etc. And if her language doesn't make sense, I 'd like to confirm whether she's had strokes or what is causing that.

I say mom needs some proactive caregiving.
Matters of hygiene can't be ignored simply due to someone's age.

If she can't do it, someone else has to or it's neglect.
Don't mistake "won't do it" for "can no longer do it" due to physical and cognitive decline.

When was the last time she was seen by a doctor? There is no information posted about your situation with your mother. She could be in a later stage of dementia.

Sometimes people with advanced dementia (whether it's Parkinson's, Alzheimers, Lewy Body, etc.) will sleep a lot. But this is not something you can diagnose at home.

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