I'm severely flat footed (wet footprint has no arch) and standing more than a few minutes starts to hurt my feet. Anyone else flat footed who tried a standing desk?
I'm sure the internet has more ideas in case you're not into running.
As with any of these types of issues it'll take dedication to fix, but if you truly can't stand for more than a few minutes the benefits should more than make up for that.
I wore running shoes, stood on a thin pad (the floor is hard tile), and took sitting breaks in a bar stool about 3 times a day for 20 minutes. I also had a bar about 15 inches off the ground for me to put a foot up on (this is a must as far I'm concerned).
Basically if you are wearing shoes you can walk/run in, they should be good enough for standing.