Mom with dementia won't use the restroom, instead sits in her chair and poos or pees in her diaper! Any advice?

Infinity, depending on how severe your mom's dementia is, this is part and parcel of the deal. They forget how to do things, forget that certain sensations mean they have to use the restroom, and sometimes even lose the sensation of "needing to go".

Since she is already using protective garments (diapers), it sounds like her dementia is relatively advanced. My own mother's dementia was considered mid-range, and she did the same thing. 

Trust me, many of us have been there - we understand. Feel free to come back and post more info about your mom's situation - you don't mention if she's living with you, you're living with her, if she's in a nursing home or assisted living - so it's a little hard to give advice, but please know we understand, because we've all been there, to some extent.

I know it's hard, but that's what the diaper is for. Be grateful she's not defecating all over the house and smearing it around. It could always be worse. God bless, hang in there.

Your profile says she is living at home --- yours or hers? Is someone in the home around the clock? I had my Mom in Memory care (MC) and the aides there brought each resident to the bathroom on a regular basis. Upon arising, before lunch, before dinner and before bedtime. AND of course, as needed. Sometimes this helps regulate the resident. Can you try that as well?

It's not just happening in your world, but every one's. My mil who has lived with us since November 2017 does this and more. She was also having "accidents" when she was living on her own in her own home. Sometimes she takes her pants down including her Depends and poos on the chair or the tv table or wherever it is convenient for her. No, this does not make me happy. I have ocd and I am also on disability for a brain stem issue so there is a lot of things going on. But, you are not alone. I have no answers for you. We are all trying to get through this. And it seems that every day or every minute is different. Hang in there! I use this site to vent.

Pepsee is right. It could be SO much worse. Unfortunately and as distasteful as it is, changing diapers and all that involves is part of the “caregiving experience”. Even home health aides can’t help with that unless they’re 24/7. If you don’t already have them, get surgical gloves. They’re sold by the box in just about every drug store. Wear them whenever dealing with her. Keep a tub with wipes, diaper cream, soap, washcloths and towels in a convenient place.

You can make caregiving easier for her. Always keep in mind that she can’t help it and if she had s choice, she’d be using the toilet as she always has.

Mom has started to do this more and more. She normally would want to go to the bathroom often. The other day, she wanted to go and when we got in the bathroom, she said that she already went and "Isn't that something?".. (She has aphasia and hardly ever says anything that makes sense.) But, what I noticed in the past few weeks is that she won't even try to go when she sits on the toilet, even pooing. She just sits there. I don't know what to expect with all this. Is this a late-stage dementia thing?

Mapotter - yes, this is definitely a dementia thing - not necessarily late-stage, though. It varies from one person to the next and there's really no rhyme nor reason to it. My mother was considered to have mid-stage dementia - she would forget how to do things, forget names, forget who lived where or who this or that child belonged to - but the she also had the loss of continence that sometimes seemed almost intentional. I could be sitting with her, visiting, and she would say she needed to go to the bathroom. I wasn't allowed to help her (NH rules), so we would ring for a CNA to help. Because they were chronically short-staffed, it could be 30 minutes or more before they'd get to her - but even so, within 5 minutes of ringing the bell, Mom would be straining and pushing, raising up slightly on her chair - filling that diaper. It was pretty uncomfortable to sit there and watch her do that, knowing that I couldn't help her get to the bathroom and she apparently couldn't control the impulse to go. At first, I thought she was doing it intentionally, but then after I asked her to wait for the CNA to help her a couple of times, and she gave me that blank, dementia stare while still defecating into the diaper (you know that stare if you've seen it), I knew that she truly didn't really understand what she was doing and why it was a problem.

Wow, today was the first time I ever saw the “blank stare”. Mom got a very strange look I’d never seen before when the nurse tried to give her meds. She had to keep telling her to keep them in her mouth and swallow, and she finally got through to her and she swallowed. The nurse said that Mom gives her that look once in a while right before spitting them out. It was very strange. I wonder why the med dispensing triggers it.

Susan, hmm, this blank stare discussion is very interesting, and sorry to hijack the original question. I never knew this was “thing” until I ran across it in this discussion.  When I witnessed my first blank stare yesterday, Mom had been napping, and the nurse woke her up to give her meds. I wonder if that sudden awakening, then immediately being asked to open her mouth, although done very kindly, may have been too much for her sleepy brain to process. The nurse said she recognizes the stare now (she calls it The Look) and has to really try to administer the meds when that’s happening. I think I might suggest that if moms napping, she awakens her a few minutes before trying next time and see how it goes. It’s pretty important to get those meds down and not spit out...they can’t/won’t try a 2nd time. 

Mapotter, maybe your Moms meds could be ground and given in a spoon of pudding or ice cream, then washed down with a sip of tea or milk. It’s easier than asking them to swallow whole pills. You have to make sure that the specific pills should be ground, for instance Moms namenda time release capsule must be opened and sprinkled, not ground up.