If a hematoma develops after a blood draw, it is recommended to apply local heat to relieve the pain after 24 hours, pay attention to rest, and be careful not to engage in strenuous activities until recovery. Because blood sampling is an invasive medical operation, it is normal for the blood vessel wall to become spasmodic and painful due to stimulation after blood sampling. It does not matter if the pressure after the blood draw is not timely or not in the correct position and the time of pressure will not cause subcutaneous hematoma, which can be absorbed and recovered normally after a few days, mainly it is recommended to take more rest to prevent the phenomenon of hypoglycemia. Remember not to randomly knead the blood extraction site, it is likely to produce new subcutaneous bleeding and make bruising and swelling worse. It is also important to protect the skin at the bleeding site to be clean and dry, and to avoid getting wet as much as possible. The diet should be supplemented with nutrients, such as eggs, wolfberry cinnamon, red dates and other blood-supplementing foods.