Purple Blotches on my arms?

Purpura, often called Senile Purpura, are a common benign condition of recurrent bruises that form on the backs of the hands as well as the tops of the forearms and shins as a result of minor trauma.  This condition goes by other names – Bateman purpura (named after the British dermatologist who first described this condition) and actinic purpura (since it is associated with chronic sun damage).

Men and women are equally affected, and it affects 10% of patients 50 years or older. Those who are affected with this condition often admit to seeing these bruises come and go in the past.

These flat blotches commonly start out red and then gradually change to purple and gradually darken and eventually fade over a period of weeks.  These differ from regular bruises in that there is often no memory of any significant trauma that may have caused them.  

The skin on the hands and forearms will naturally thin due to the normal aging process and chronic sun exposure also contributes.  The skin becomes thin and no longer offers support and protection of the blood vessels within the tissue. The superficial blood vessels also become thin and fragile.  Those blood vessels become vulnerable and minor trauma can cause them to tear and rupture causing leaking of blood into the surrounding skin and the bruising is then created.  Brown discoloration can subsequently form from deposition of a component of red blood cells called hemosiderin.  It is not unusual for people who have this condition to then be left with persistent darker brown skin in those areas.  

Certain medications can also be a cause of senile purpura.  Medications that thin the blood like aspirin and Coumadin and certain vitamins and supplements, use of alcohol, and use of corticosteroids (topical, oral, or inhaled) can also bring this condition on.  

The good news is that this is not a serious or harmful condition but is not easily treated.  If medication is the cause the patient can discuss possible changes with their healthcare provider.  Makeup can be used to camouflage the lesions.  Application of anti-aging/anti-wrinkle creams can also be tried in an attempt to thicken the skin but does not seem to work as well as most would like.  

Daily application of sunscreen is always a good idea and if started early enough may reduce the likelihood of developing this condition later in life.