It seems that you are having ecchymosis
You should under go various blood tests to rule out blood diseases.
If they found to be normal, the consider the blotches as senile purpura
It may be due to fragile capillaries.
Take vitamin C
Apply thrombophob oint.
Moisturising agent like liquid parrafin or urea may be appalled on dry skin
I hope you got my answer.
Dr. Ilyas Patel MD