A few years ago, when Mom was living alone, she got to a point where her sense of "time of day" was messed up. She could no longer understand what the clock said or think to look at it. Even now she can still read her watch, she can tell me "3:30" but her comprehension of "3:30" is gone.
This really got messy because at that time she was also managing her own medications. She would have her breakfast meds with breakfast. After her nap, she would wake up and take her breakfast meds again. Later she would eat diner and take her night meds. Then she'd fall asleep in front of the tv, wake up and take her night meds again. I'm not saying this happened every day. But it happened a lot.
This was when she was living totally alone, when I would check on her every two or three days.
I tried to help her by setting up weekly pill boxes with AM and PM sections. I would label each section "Mon June 6" hoping she could correlate it to the big digital clock in the middle of her kitchen table, right there beside the pill box. At my next visit there would still be too many empty pill slots.
Then I took away all her extra pills and left only enough until my next visit. Hoping that the blizzards would let me return in time. Mom would call me the next day and say all her pills were gone.
Then I arranged for visiting home health aides. They would come in the morning, make her breakfast, guide her to the shower, dispense her morning meds, make her lunch for later, and set out her evening pills. I would get angry calls from Mom that she didn't have any pills. She had already taken them, but forgot.
At that time Mom was not taking any heavy-duty medications. But still, overdosing on anything is not a good thing.