My experience was very much like that of @CallieAndToby22. My BP runs very low, and my neurologist felt this would help raise it. When I took it, I felt "buzzy," shaky, and overstimulated, and not at all well, and then I felt exhausted after it wore off. I have neurally-mediated hypotension, not POTS, and I'm also ridiculously sensitive to medications, so I wasn't sure that Northera would help me, but I'm glad I had an opportunity to try it.
I find that the things I have tried to raise my BP (Ritalin, Adderall, Midodrine) all have had similar effects: my BP might go up temporarily while the medication is in effect, but I don't feel well at all, and I crash very badly afterwards.
If you do decide to take it, good luck, and I hope you find something that helps!