There are many causes of purpura including non-disease factors such as some drugs penicillin and disease factors such as thrombocytopenic purpura. Purpura is a subcutaneous hemorrhage caused by the exudation of red blood cells from blood vessels into the skin, connective tissue or mucous membranes. The main causes of purpura are drug allergy, such as penicillin, cephalosporins, sulfonamides, and other drug allergies and induced purpura. Disease factors such as thrombocytopenic purpura may be produced in the body of the anti-platelet antibodies to destroy their own platelets leading to this disease, but also may be a viral bacterial infection affects the platelet production and life expectancy, thus leading to thrombocytopenic purpura. There are many causes of purpura, it is recommended to go to the regular hospital in time to check the symptomatic treatment, so as not to delay the condition and miss the best treatment period.