I don't mean to scare anybody, but my POTS symptoms began shortly after getting the flu shot a few years ago. I will never get the flu shot again--but primarily for superstitious reasons as a result of this. I bet this is just coincidence, however. Did anyone else notice their symptoms beginning shortly after receiving the flu shot? Again, probably just coincidence. I have been meaning to post this question, just never got around to it because of the obscurity of the theory that a flu shot can cause pots or possibly exacerbate it to the point that one notices their symptoms.