Black and blue on the leg is often due to local bruises, increased capillary fragility, etc., caused by the following: First, local bruises: when the leg is bumped after the capillary rupture, when the bruise blood absorption process can appear black and blue, generally can be localized hot compresses, which will help dissipate bruises, but also can be coated with yunnan baiyao, safflower oil, etc. to help recovery, part of the patient can also be applied to the outside of the traditional Chinese medicine For treatment; second, increased capillary fragility: when the blood vessels are too brittle, the local can appear easy to bleed, need to go to the hospital to improve the relevant examination, such as ultrasound to clarify; third, other: may be caused by low platelets, there may be poor coagulation caused by the function of the blood, need to go to the hospital for clarification. During the treatment period, you can’t drink drinks containing alcohol, don’t eat too spicy food, and don’t do too strenuous exercise.