My mom's personality has changed considerably. She was always kind and caring, now she is paranoid and mean. Is this common?

Lealonnie1 has given excellent advice here. I will add three pieces of advice based on my very similar experience with my husband in his initial stages with dementia.
1. Go with your mom and dad to her initial doctor’s appointment. Take other supportive siblings if appropriate. Her doctor needs to hear all perspectives on her behavior. Your mom will not be a reliable reporter. In my situation, Our children and I had to talk to the doctor alone because my husband accused me of telling untruths about his behavior. It also made him angrier at me, like I was “telling on him.”
2. In addition to anti-anxiety medication (lexapro for him), my husband responded well to a low dose anti-psychotic, in his case it was Seroquel. This quickly addressed his paranoid behaviors and our relationship became less threatening to me. Similar to your dad’s situation, my husband thought I was an intruder and wanted me out of the house.
3. Encourage your dad to join a support group and this forum where he won’t feel alone in his situation. Read and research as much as you can about this disease and educate/support him and your mom. My husband has progressed to late stage and is in hospice care here at home. I now have outside caregivers helping me.

It’s now five years since those frightening early stages. Our children have been and continue to be a blessing to us in this heartbreaking journey. Bless you for caring and supporting both your parents!

Your mother has dementia/ALZ and so, this behavior she's exhibiting goes with the territory; paranoia, feeling unsafe in her home, and that people are in her home that shouldn't be there, and that stealing is going on. Her doctor needs to be notified of this new behavior, so she can be checked for infections like a UTI or other organic issues first, to see if that's at the root of the change, and if not, perhaps anti anxiety meds can be prescribed. My mother had great results with .25 mgs of Ativan when her dementia behaviors (mostly Sundowning in the afternoons) got pretty bad.

I suggest you read this 33 page booklet (a free download) which has THE best information ever about managing dementia and what to expect with an elder who's been diagnosed with it.

Understanding the Dementia Experience, by Jennifer Ghent-Fuller 
https://www.smashwords.com/books/view/210580

Jennifer is a nurse who worked for many years as an educator and counsellor for people with dementia and their families, as well as others in caring roles. She addresses the emotional and grief issues in the contexts in which they arise for families living with dementia. The reviews for her books are phenomenal b/c they are written in plain English & very easy to read/understand. Her writings have been VERY helpful for me.

The full copy of her book is available here:
https://www.amazon.com/Thoughtful-Dementia-Care-Understanding-Experience/dp/B09WN439CC/ref=sr_1_2?crid=2E7WWE9X5UFXR&keywords=jennifer+ghent+fuller+books&qid=1657468364&sprefix=jennifer+ghent%2Caps%2C631&sr=8-2

She also has published a workbook entitled, “It Isn’t Common Sense: Interacting with People Who Have Memory Loss Due to Dementia.”

https://www.amazon.com/Isnt-Common-Sense-Interacting-Dementia/dp/1481995995/ref=sr_1_4?crid=2E7WWE9X5UFXR&keywords=jennifer+ghent+fuller+books&qid=1657468655&sprefix=jennifer+ghent%2Caps%2C631&sr=8-4
 
 Another good reference book is The 36 Hour Day which has some good info on dementia/ALZ and will answer on the spot questions you have that will crop up.

Teepa Snow has some fantastic videos on YouTube about how to speak to dementia sufferers and how to interact with them to achieve the best results.

Here is a list of useful tips from the above mentioned e-book I found to be excellent:

The “Dont's”
· Do not reason and argue
· Do not demand that they reason or problem-solve
· Do not demand that they remember
· Do not demand that they get their facts straight
· Do not correct their ideas or scold them
· Do not reorient them
· Do not think that they are being uncooperative on purpose
· Do not think that they really do remember, but are pretending not to
· Do not use a “bossy” dictatorial attitude in care
· Do not act with impatience

The Do's
· Enter into their frame of reality, or their 'world'
· Be aware of their mood or state of mind
· Use few words and simple phrases
· OR use no words, just friendly gestures and simple motions
· Do everything slowly
· Approach from the front
· Wait for a slow response
· Constantly reassure them that everything is 'OK'
· Keep people with dementia comfortable 'in the moment' - every moment
· Maximize use of remaining abilities
· Limit TV or radio programs which they may feel are frighteningly real
· Maintain privacy
· Provide a safe physical environment

Language Needs
· Use short words
· Use clear and simple sentences
· Speak slowly and calmly
· Questions should ask for a “yes” or “no” answer
· Talk about one thing at a time
· Talk about concrete things; not abstract ideas
· Use common phrases
· Always say what you are doing
· If they repeat their question, repeat your answer as you did the first time · Give them a longer time to process information
· Wait patiently for a response
· Be accepting of inappropriate answers and nonsense words
· Speak softly, soothingly and gently

Best of luck!

If you have not called her primary doctor about the recent changes, please do and request a lab order for UA (urine analysis). Some geriatric act strangely as you state when they have a UTI (urinary tract infection). She may need to be put on antibiotics. It is very common for geriatric women to have mood swings, confusion, hallucinations, paranoia, etc if they have a UTI.....good luck

It seems like at some point, we all have to go through the misfortune of a parent or parents who have lost their minds. It makes it all the worse when they become mean and or violent. Sometimes I think we live too long, where quality of life goes out the door along with the bathwater. Often, we feel helpless and unable to intervene for many different reasons. I wish there was a magic wand that we could all wave, to take these painful situations away from us and our loved ones. These are things that life does not prepare us for, and there are very few resources available in this day and age when there are shortages of healthcare workers and exuberant prices of long-term care facilities. I am grateful for this website, as I feel so many of us have so much in common with these extremely difficult situations. Thank you all for being there, and by the grace of God maybe we will all get through this somehow together.

This is my parents 3years ago. Very similar. First my sisters and I manipulated my mom in giving us (not my dad the POA) to both medical and non medical. My dad was okay with this arrangement and we did the same with my dad (we were his POA). We succeeded and then established a trust for my parents. Second, we came up with a fib and moved my dad in one of us kids and my mom stayed at their house (and my sister moved in to take care of my mom). We placed my mom on 1mg risperidone to take care of paranoia hallucinations etc (make sure other meds are not causing this as we found my mom toprol heightened this and we switched toprol to amlodipine). My mom was night and day with risperidone. It took a month or so before my mom was more agreeable and easy to talk to. My dad has early signs of dementia too so we started him on 1mg risperidone too and it worked (my dad was narcissistic and belligerent and all this was gone). Fast forward 3years later (it was tough keeping them separated - holidays separate and we constantly had to hide my dad’s whereabouts to my mom. Unfortunately as my mom’s Alzheimer’s progressed she forgot how much she hated my dad. Recently, we brought them back together (small reunion) and my mom was not upset at all. It couldn’t be better. When my mom asked where my dad went we all said just at work. He was assigned somewhere. It was a sufficient fib. My sisters and I made sure we were the POA for both my parents asap as my mom was almost swindled. I hope this helps. My parents (married 56years) are now living together again under my roof, under my supervision. Time helps but it’s also time lost that they could have enjoyed each other’s company. Prayers 🙏

As others have said, this is dementia. There are legal things that you must get rolling and she must get care Asap! Please proceed and don’t give credence to the crazy things she says. That’s the disease talking.

It sounds like either your Mom has depression or is well on her way with dementia.

I suggest you take her to a geriatric doctor to get a health assessment. However, if she was like my Mom, that just increased the anxiety until I could get her to a doctor that she respected.

What does your Dad think about what is happening? Ultimately, any actions taken will affect him too.

This kind of paranoia is not unusual with dementia. People "forget" how to interpret things and people around them. Does she have caregivers or housekeepers coming into the house (are these the women she referred to)? It sounds like she is not recognizing your dad any more and is close to the point where she should no longer be handling money. Speak with her doctor about medications that might calm her. Sometimes people with dementia also get physically abusive (hitting and kicking). Make sure her paperwork is in order while she is still able to sign legal papers. She needs to set up powers of attorney for financial and medical matters, a living will with her advance medical directives and a will, if she has assets. You may need an attorney specializing in elder law to do this. Would it make sense to place her in a memory care facility? Professional staff know how to deal with paranoia and suspicion and can also help advise whether the medications are working. I think your mother's state must be very disturbing for your father. It may be better for both to separate them. He can try visiting later; the current stage is likely to pass, and she'll move on to another stage of dementia. Sadly health and mental health only decline with dementia. If you decide on a facility, try to find one close to you and your father so that you can oversee her care and visit frequently.

Sounds like dementia.
Dementia is NOT "just memory"..it is BRAIN DAMAGE. The brain is dying and parts of it become very hard to access, memory, behavior, understandings and rationals...
She needs assistance and compassion.

Oh yes, I have been in your boat, which often felt like a sinkig boat at that. My mom, once kind and caring, became irrational, paranoid, and delusional, once Alzheimer's hit. Hubby and I took care of her for 5 years. Once, we went to a fast food place and she loved the breakfast there. She took her leftover coffee home. We got home, and she said it was poisoned. I said "Mom, this is the same coffee that you just drank a few minutes ago and loved it," but she was so headstrong about it, that I took the coffee into the kitchen, put it in one of our cups, and she loved it. I agree with the others; you might need to take her to a doctor for an evaluation. I even wrote a book about our travails called, "My Mother Has Alzheimer's and My Dog has Tapeworms: A Caregiver's Tale." I tried to write it with humor and heart, since you need both in life, and particularly dealing with Alzheimer's/dementia (if that's what your mom has). My mom also had hallucinations, both visual and auditory. I learned, especially with the auditory ones, the one voice she really needed to hear, was mine. I could comfort and reassure her, but I couldn't reason with her. Good luck.