I was bedbound and unable to talk at all for about 4 months. I am still completely bedbound but in the last 2 months I have started to regain ability to talk up to a couple of minutes per day but my chest/breathing weakness tends to worsen throughout day. So I decided to try clonazapem in the late afternoon and straight away I noticed about an hour after taking and lasting several hr that I could take deeper breaths, hold my breath a little, talk more easily, etc. The other thing I notice is that if I take it about an hr before a bowel movement using bedside commode that I can often start using computer again almost immediately when previously I would often have to lie still for several hr and get all sorts of symptoms I assume to be ANS related.
I don't have the chest weakness symptoms so I can't help you there, however, I also had severe worsening of neurological symptoms from standing up, using a computer, or hearing music etc. Clonazepam definitely helps with that.
My idea is that severe POTS triggers neurological symptoms and clonazepam is nervous system depressent so it helps there, but I am very confused how such two very different things like standing up and seeing movement on screen can lead to same type of neurological overload.
My mother used to wrap my legs before I would stand up and that helped me make a few steps per day but now I am too sensitive to touch and too weak to walk. Maybe higher dose of clonazepam would help but, just like you, I am worried about dependance and so am keeping the dosage as low as possible to prevent delirium.
I'm sorry I can't be of more help but I am as lost as you are.