Overview
Bruises change color as they heal.
Easy bruising can signal a bleeding problem.
When to get medical care
Causes
Causes include injury, blood thinners, aging, and bleeding disorders.
OwieClear has pages on 4 conditions that can cause a bruise. Each shows how soon to get care.
Common causes
- BruisesOften treated at home
Bleeding under the skin from a bump, causing a mark that changes from red or purple to blue, green, and yellow as it heals over 1 to 2 weeks.
Less likely causes
- Anemia (low red blood cells)See a doctor if it doesn't get better
Having fewer healthy red blood cells or less hemoglobin than normal, so the body gets less oxygen.
- AngiosarcomaSee a doctor if it doesn't get better
A rare cancer of the lining of blood or lymph vessels.
- Blastic plasmacytoid dendritic cell neoplasm (BPDCN)Often needs care today
A rare, aggressive blood cancer, most often in older men, that usually first shows as bruise-like purple or brown patches or bumps on the skin.
What you can do at home
- Ice it.
Medicines
Depends on cause.
At the doctor
Blood tests if needed.
Questions you may be asked
- Medicines
The exam
A skin exam.
Tests
- Blood count
- Clotting tests
Prevention
Prevent falls.
- Clear walkways
Check your symptoms
Most symptoms have more than one possible cause. The symptom checker looks at all of your symptoms together, plus your age, and shows how soon to get care.
Sources
Last updated 2026-11-13.