Assuming you were doing the exact same activity, is your heart rate higher in the morning, or in the evening? Are your POTS symptoms in general worse at one of those times than the other? My HR and POTS are best first thing in the morning, and then get progressively worse as the day goes on. By evening it can be really bad. On an average day, my HR walking around in the morning can be around 105. By evening, 125 - 130 is more typical (and on a bad day, it can be far worse than that). ...But from what I've read, this seems to be the other way around for most POTS patients. I also haven't had any noticeable help from high compression stockings, increased salt/water intake, etc., despite visible evidence that my blood is pooling in my feet sometimes when I sit/stand too long. Keeping my legs crossed rather than hanging down while sitting does help a lot, though. Maybe my body is so out of whack that the more subtle interventions can't do enough to make a noticeable difference. Maybe my problem is related to cortisol and I get a boost in the morning. Maybe I'm still overdoing it with the tiny amount of activity I have during the day, and my body's worn out by nighttime. Who knows. Anyway, I've been curious how much of what's wrong with me on that front is different from the standard, and how helpful other interventions may or may not be as a result, so I wanted to ask if anyone else here has O.I. symptoms that are worse later in the day. And if so, have any medications been helpful to you in managing them? Were you able to definitively identify what the problem is for you, or come up with a way to help it?