To relieve edema, exercise and sweat it out.
The other way to relieve edema is acupressure. Press on the swell and see it go down. Essentially, one presses down on the swell to disperse the accumulation of the liquid under the skin.
There are dehydrating herbs that are used in Chinese medicine such as licorice (gan cao), ginger, garlic, black pepper, aloe, black and bitter sesame oil, dong quai (Angelica sinensis), ginseng, dang sheng (Codonopsis), di huang (Rehmanniae) etc.