Taken directly from WebMD Health.
Bruising easily is not necessarily an indication of a serious problem. Women are more prone than men to bruise from a minor injury, especially on the thighs, buttocks, and upper arms. Sometimes easy bruising runs in families. It is common for older adults to bruise easily from minor injuries, especially on the forearms, hands, legs, and feet. This is because of the skin changes that occur with aging.
Most bruises heal within 2 to 4 weeks. As bruises heal, they often turn colors, including reddish blue, purplish black, and yellowish green. Sometimes they move down the body from gravity. A leg bruise usually will take longer to heal than a bruise on the face or arms.
Occasionally easy bruising is a sign of a health problem and may be caused by:
- The side effects of a medication. More common medications include aspirin, other nonsteroidal anti-inflammatory drugs (NSAIDs), and blood-thinning medications (anticoagulants).
- Other medications that can affect clotting and therefore cause bleeding as a side effect. Examples are some antibiotics and medications to treat heart problems, cancer, depression, anxiety, and allergies.
- A bleeding or clotting disorder, such as hemophilia, von Willebrand’s disease, thrombocytopenia, or a less common bleeding or clotting disorder.
- Other medical conditions that affect clotting, such as an infection or nutritional deficiency.
Bruises that do not go away within 4 weeks of an injury may mean that:
- A medical problem is preventing normal healing.
- An injury is worse than you suspected, especially if you still have pain.
If you are concerned about how easily you bruise, or if bruises don’t seem to be healing normally, a health professional can evaluate the cause of your bruises and recommend treatment.