My hands and feet started swelling when I was 13. I've had every medical test known to man... Even went to the Mayo Clinic. They confirmed that everything was normal on me except that I retained very large amounts of fluid. They diagnosed the condition as idiopathic edema... swelling for no known reason. They say there is no cure, just learn to live with it.
I've tried everything that comes down the pike and have for years, I am now 52. Probably not what you want to hear.
I take a combination of water pills daily to keep it somewhat under control.
Good luck, and let me know if something actually works for you!