Lower lip long black spot may be caused by bad habits, pigmented nevus, melanoma and other reasons.
1. Bad habits: often biting lips with teeth in life, too strong or repeating this action for a long time may lead to bleeding under the mucous membrane of the lips, and when the color is darker, it will look like black spots, which may appear as black spots on the lips.
2. Pigmented nevus: it is a benign proliferation of melanocytes, which can also lead to black spots on the lower lip when it occurs in the mucous membrane of the lips.
3. Melanoma: it is caused by excessive proliferation or malignant proliferation of melanocytes, and its early appearance is similar to that of nevus, which can also be manifested as dark spots on the lower lip.
Black spots on the lower lip may also be caused by exogenous coloring, abnormal adrenal cortex function, etc. It is suggested that patients should consult doctor in time and follow the doctor’s instruction after clear diagnosis.