Hi John,
What does your doctor say about this? I am guessing that this is a bit of edema from being sedentary. The act of walking helps to pump blood back up your legs. The pill you mentioned is probably a mild diuretic. I know you are wheelchair bound but is there any excerise you can do?
You might try to have Robin gently massage your legs while they are elevated. Also, if you have access to a pool (you may be unable to do this due to mobility) that can help. For some reason the counterpressure from the water helps. Try to avoid salty foods. Watermelon and celery are mild diuretc foods than can help too.
Some people take a mild diuretic all of the time to alleviate mild edema. Edema can be uncomfortable. Ask your doctor how to manage this and make sure he knows how often you have it.