Spontaneous Bruising

Top 5 Explanations For Unexplained, Spontaneous Bruising

Unexplained or frequent spontaneous bruising is seldom an indication of a serious health condition. Bruises can occur from an external impact upon the body, of even the slightest degree. They can also be related to contusions or ruptures beneath the skin that result in broken blood vessels. Another reason for such bruising is blood thinning and deceased clotting properties.


Let’s review the most likely causes; these are usually not indicative of a health problem requiring medical attention.

  1. Thin skin - The less depth there is to the outer layer of skin the easier it will bruise, even to the point that something you don’t even feel, maybe a slight bump on the car door, will leave a bruise.  These bruises usually are on the arms and legs because they don’t have as much fat to protect them as the parts of your body. 

  2. Some topical creams or ointments, which are used for itching, skin problems such as rashes, poison oak, insect bites or chronic problems like eczema can reduce the elasticity and strength of the skin.  And again, thin skin leaves one prone to spontaneous bruising. These products may be over the counter or prescription.

  3. Reduced blood clotting caused by drugs or supplements that thin the blood.  Some examples are anticoagulant drugs for heart disease and preventing strokes, Plavix or others in that category, fish oil, and some kinds of ginkgo biloba.

  4. By virtue of being in a group of people that has thinner skin, you are more likely to bruise. The two largest groups tending to have thin or delicate skin are females and the elderly.  The skin just gets thinner with age.  That’s why you often see elderly with bruises on their hands and arms.

  5. Vitamin deficiencies - A lack of sufficient vitamin C, which is needed for healthy blood capillaries, and/or insufficient vitamin K, which is needed for healthy blood clotting.

If bruising does not fade after a few weeks, or you don’t seem to fall into the profiles above, it may be time to seek a professional opinion. If you have a bruise that is very large and appears for no reason, or if you have been getting nose bleeds, bleeding from the gums or elsewhere in addition to the bruises, this could be a sign of blood platelet problems or blood disease.  A doctor will check platelet levels in this case.


Before your appointment, list all the vitamins, supplements, prescription, and over the counter drugs you take, to help your doctor diagnose the problem.  Make note of any history in your family of hemophilia or blood disorders, or similar susceptibility to bruising in family members Your diet may be related to bruising so make notes regarding what you usually eat.  With this anecdotal information and specifics on medications you take, a doctor may realize something that you missed.  Or they may suspect and test for other problems. Either way spontaneous bruising is not a cause for worry, and is usually quite natural.