Nails with black lines may be caused by nails suffering from impact of foreign objects, onychomycosis and other reasons, and need to be treated with medication and surgery according to the cause.
1. Trauma: Nail trauma, such as the impact of foreign objects or extrusion, resulting in the rupture of capillaries under the nail plate, can form a black line in the nail plate. This situation does not need special treatment, you can first observe and wait for its slow recovery.
2. Nail nevus: it is a kind of dark pigmented nevus existing in nail bed, which may have certain possibility of malignant transformation in the later stage. You should go to the hospital as soon as possible to rule out the possibility of malignancy. Generally, it can be observed clinically, and if it is wider or suddenly becomes bigger, it needs to be removed surgically.
The appearance of a black line on the nail cover may also be other conditions such as liver and kidney function abnormalities, etc., need to go to the hospital as soon as possible, according to the specific conditions of the doctor, to formulate individualized diagnostic and treatment plan, so as not to delay the condition.