Hi all, I guess you can see that we are not all alike, despite some commonalities. None of us are easy cases, certainly (which is one reason we see people for a week at POTS Care, and often need to continue to work with them when they leave). I know how hard it can be to try to find answers to our individual cases. 🙁 I did want to mention that choline doesn’t cross the blood-brain-barrier. Alpha GPC does, is needed in MUCH smaller quantities than choline, but is also only one component that we found was important in Parasym Plus. The balance of all of the ingredients was critical, and was the only way to effectively boost the vagus nerve AND boost acetylcholine for the brain. Currently, I am on Zyrtec, and Parasym Plus has no problem overriding its anticholinergic effects. Hope this helps!