My 85 year old mother with moderate dementa is getting worse by the day as far as her behavior. She's refused her meds for three days in succession this time and is "off the chart" agitated. She's convinced that everyone is trying to kill her, including me (her daughter) and her sitter so we can get her money. She's been praying out loud that God would make something bad happen to me and my husband! She recently had a UTI and was barely eating or drinking for 2 days and everyone thought she was dying. Nursing home called in Hospice then she rallied quickly AGAIN and no one seems able to do a thing with her, including Hospice. She is on 2 medications for high blood pressure and one for hypothyroidism which she is not getting either. Heart rate well over 100. All I know to do is pray for her.
Continue to pray for her and know that when it's her time to transition, she will. You've done your best for her, and that's a wonderful thing. Wishing you all the best as you work your way through this difficult situation you're facing.
I'm not sure sure about sodas either. Some can be taken with a soda drink, but again there's the chance of maybe weakening the meds.
My own mother recently accused me of "trying to kill her." She was having trouble with constipation and I was suggesting different things she might be able to try, and she doesn't even appear to have dementia and still lives alone. Although I have begun to notice a few warning signs of possibly early stages of dementia. The thing is, she sometimes say things to my other siblings on the occasion they decide to stop by her place or call and they, not being around to see those 'empty moments' in her eyes or mind briefly wandering off, they don't see what I see because I'm around her more they might take her at her word. So they take her at her word. I thought she was joking, but realized she wasn't when I looked up and saw she was serious.
Now if I take something over I've cooked for the day I eat some of it in front of her. Sometimes she'll still refuse it though. But since she still cooks her own food mostly, I'll just sit there eat what I took over hopefully so she won't think there was anything in the food or I'll take it back home.