Bleeding into the skin from damaged blood vessels causes discoloration and tenderness of the skin, which we call a bruise. Because the skin is not broken, there is no risk of infection. Bruises usually occur after an injury caused by blunt objects. Unexplained bruises can indicate a bleeding tendency (exception: "unexplained" bruises on the shins are usually not a sign of a bleeding tendency because people commonly bump this area and then forget that they bumped it).
Bruises change colors over time from reddish to bluish to yellowish before the skin fades back to its normal color.
Apply a cold pack or ice in a bag to the bruised area for 20 minutes. No other treatment should be necessary. Take acetaminophen or ibuprofen for pain. Don't use aspirin because it may prolong the bleeding. After 48 hours apply a warm washcloth for 10 minutes three times a day to help your skin reabsorb the blood. Bruises clear in about 2 weeks.
Do not open blood blisters because it will increase the possibility of infection. The blisters will dry up and peel off in 1 to 2 weeks.
Call IMMEDIATELY if: