I have a theory that is untried and unproven, but it might be worth a try, if things are that bad. I have long suspected that hormones are involved. I have not reached any conclusions about cause and effect. But if hormone therapy would get you out of a serious problem, it might be worth discussing with your doctor.
What comes to mind is adrenalin. If your problematic perseveration is 24/7, then you could receive a shot in the doctor's office. If it works, you could get an epi-pen. The problem would be getting the doc to give you a shot when there is no medical reason to do so.
Theory #2 - I have a weighted blanket. It *instantly* makes me calm, no matter how far into meltdown or panic I may be. Here again, I suggest trying it. Again, if your problem is 24/7, you don't have to try it in the office until you know it works. Hint: does the dentist's x-ray apron comfort you? If yes, a weighted blanket might be worth a try. I got one as wide as my whole bed - if I had it to do again, I'd just get one as wide as a single bed.
I got my weighted blanket here -
Dream Catcher Weighted BlanketsPlease keep in touch and let us know how you go.
I currently undergo hormone treatment for other reasons, and I have no health insurance so I can't really see a doctor.