My husband s feet have been swollen since yesterday. He says his feet hurt, and feel tight. The swelling goes all the way up to his shins. He s constantly cold, and has slept most of today away. He has a scar from a previous injury from 2004, but when checking out his swelling, I noticed a small, black area has appeared in the middle of the scar. He has just started on Oxycontin and Fentynol patches for a back injury. Could either of these medications be causing the swelling? What about the black mark? How do we get the swelling down and him feeling better?