Black eye treatment. The initial treatment of "black eye" is ice packs to reduce swelling. Anti-inflammatory medication like Ibuprofen will reduce the pain. After 3 days, however, the swelling should be gone, and the only remaining symptom will be the discoloration, which may still be changing colors from black-purple to yellow-green. The only thing that will help in this phase is warm compresses to speed up healing.
Bruises. Bruises change in appearance over time, and it is possible to tell by looking at a bruise how old it is. When it first appears, a bruise will be reddish looking. By one to two days, the reddish iron from the blood undergoes a change and the bruise will appear blue or purple. By day six, the color changes to green and by day eight to nine, the bruise will appear yellowish-brown. In last 2-3 wks.
Patience. Not much to do but to let it run it's course.