Need help on how to navigate sister going through psychosis
My sister is in her early 30s and has clear signs of her going through psychosis. There were signs here and there years ago when she claimed that a big medical corporation and her old workplace had sent people to stalk her. She had also claimed that certain food delivery drivers were stalking her too. Those delusions were only mentioned once in a while over the years, but recently it's gotten worse. Her recent delusions include high school teachers stalking her and grooming her and she started reaching out to old acquaintances she had barely talked to before and well as her high school friends who are currently her closest friends to ask for evidence about the "grooming" and "stalking". I know for a fact that this never happened.
It has escalated to the point where her friends have reached out directly to me out of concern, and she has claimed to them that she no longer wants to be friends with them, but still constantly messages those them about "incidents" from the past. She had also texted one of them that she was suicidal, which had raised a big flag and made us all tread around her with caution. I had initially thought she was only being delusional around her family and masking it around others, but hadn't realized it had reached her friends and acquaintances.
For more context, I think her psychosis was drug-induced. During early covid, she had quit her job to do a career switch and went back to school remotely. Around this time, she had mentioned to me that she had started taking antidepressants and adhd meds. Fast forward to now, she has a couple different other meds she has been taking, and I'm realizing that maybe the interactions of all these drugs or even just these meds themselves are causing psychosis symptoms. Due to HIPAA, I'm not sure how to go about this. I would like to reach out to her psychiatrist (I am also not too sure if has multiple psychiatrists and being prescribed different drugs by different ones) to let them know about her behavior and delusions.
In the past year, she has mainly been cooped up in her room. She still lives with my parents so she's taken care of with housing and meals. She only comes out of her room when she has package deliveries (she's been ordering an excessive amount of packages over the past year or two) or needs to get food/water from the kitchen. My family and I have tried to tell her to go outside more or try to socialize with her friends, and she acknowledges that she will be she doesn't end up executing any plans. Originally, we would constantly ask her about her job search since it's been a while since she graduated from her program, and she would always lie to us that she was looking when I know she wasn't. My sister's recent behavior includes more irritable and abrupt replies in in-person conversations, sounding quite emotionless and I've seen that she's ordered a lot of chocolate to the house. In some text convos towards others, she's been quite abrupt and even rude.
She does have a lot of childhood trauma with my parents so it isn't a healthy dynamic in that household, but over the years I've explained to my mom about my sister's mental health issues and I think now she's become more understanding. She also has medical trauma and parental trauma from a past medical issue that she thinks would've been life changing if it was resolved in the past. This was something she uncovered around 2020/2021 (maybe around the time she started her meds) and ever since then, she had been non-stop talking things from the past and blames my parents constantly. I had to distance myself from her since I couldn't stand always having to hear about the same triggers in most of our conversations.
I, along with many others, have told her to seek therapy over the past few years but she's always shut us down about it due to her medical trauma. At some points, I was thinking about sending her to a mental health facility involuntarily, but I looked more into it, and I think it is an excessive measure at the moment when she is not appearing to be any danger to herself or her family. I would also prefer not to since I know it can be a traumatizing experience and create more distrust towards her family. She seems to be very vengeful as she's threatened to open lawsuits again the big medical corporation (this one is fair) as well as the school district regarding the teacher grooming case.
I would love for therapy to be her first step, but if she is not willing, my family and I are not sure how to go about this. On our end, we are trying to have more positive communication with her and less invalidation of her delusions. Some of my family members and I were originally distancing ourselves from her, but ever since her friends reached out about her behavior, we've been in contact with her more and trying to suggest activities to do together to get her out of the house. I am also scared to call for a mental health checkup to our house because that will also create more distrust towards us.
I know this is a long post, but would appreciate any advice or similar stories on how you went about this!