Purpura, trauma, skin tumors, drug rashes, pigmentation polyp syndrome, etc. 1. Purpura: allergic purpura and idiopathic thrombocytopenic purpura may cause bleeding spots and ecchymosis of the skin, which may be manifested as symptoms of purple spots on the lips. 2. Trauma: extrusion and bruising of the skin and mucous membrane of the lips may cause capillary rupture, resulting in purple spots on the lips. 3. Skin tumors: benign tumors such as pigmented nevus, malignant tumors such as melanoma, basal cell carcinoma and so on. 4. Drug rash: allergic reaction caused by taking drugs, local itching, redness and swelling may occur, and there may be pigmentation after subsiding, resulting in purple spots on lips. 5. Hyperpigmentation polyp syndrome: it is a genetic disease, which will lead to an increase in melanocytes, which can be manifested as pigmented spots on the oral mucosa and the perioral area. Purple spots on the lips, it is recommended to go to the hospital in time to improve the examination, in order to clarify the diagnosis.