Bruises and hematomas both occur when a force—usually a blunt force—directly impacts the body, causing blood vessels to break open. Examples include falls, car accidents, and sports injuries.
Medical procedures and broken bones can also cause bruises and hematomas.
There are certain factors that may increase a person’s risk of bruises or hematomas:
- Older age
- Bleeding disorders, like hemophilia, a condition that causes difficulty with blood clotting
- Thrombocytopenia, or a low count of a type of blood cell that helps stop bleeding
- Alcohol use disorder
- Liver disease, or a group of conditions that lead to liver damage
- Vitamin C or K deficiency
- Severe viral infection
- Blood cancer
Certain drugs can also increase the risk of bruises or hematomas:
- Nonsteroidal anti-inflammatory drugs (NSAIDs) like aspirin
- Blood thinners, like heparin and Coumadin (warfarin), which may be used to treat blood clots
- Corticosteroids like prednisone, which may be used to treat inflammatory conditions
- Certain antibiotics, which are used to treat bacterial infections
- Certain supplements like Ginkgo biloba, omega-3 fatty acids, and garlic