Hi, @jackiepon, I wasn't familiar with POTS and doing a quick search found this site: https://www.webmd.com/heart-disease/atrial-fibrillation/postural-orthostatic-tachycardia. My symptoms don't fit this but my cardiologist diagnosed my Orthostatic Hypotension by first taking my bp in both arms and in each of the lying down, sitting and standing positions. My OH occurs infrequently and when standing, usually for some time. I immediately know to sit down because of the sudden light headedness. Until I can sit, clenching my fists tightly at my side and even crossing my legs like scissors while standing can help bring the pressure up a bit. I also take a low dose of 5 mg of prescribed Amlodipine Besylate 1/day for high b.p. Cardio told me to stop the med until my bp comes back up to 130 and that usually happens within a day or two of stopping the med. Fortunately for me, and perhaps for you, everyone is different, my sudden dizziness subsides rather soon after sitting or lying down; however, the episodes do bring on extreme fatigue but that improves as my systolic b.p. climbs back up. I know that dehydration can bring on an OH episode but I don't think that is the cause for me. I have dry mouth and kidney problems which have me drinking a great deal of water each day. Now that the condition has a name and I know what to do, I check out places for "chairs" when in stores or offices. Until getting to the cardio, those initial drops were scary!