Lichen planus is a benign growth of the skin caused by human papilloma virus (HPV-3 and HPV-5) infection. It can occur in anyone and anywhere, but is most commonly seen on the face, back of the hands and forearms of young people. Clinically, the rash is mainly normal skin color, light red or light brown flat papules, the size of rice grains to green beans, round or polygonal, smooth surface, clear boundaries, a large number of rashes, often scattered or densely distributed, some can appear homosexual reaction, such as along the scratch, along the scratches arranged in a series of beads of flat papules. The disease has a long course, and some of them remain stationary for many years. Once the human body has a serious cold, fever, trauma, overexertion, long-term insomnia, menstruation, pregnancy or endocrine disorders, etc., the latent virus in the body can suddenly develop and more rashes appear, which are not easily and quickly cured. The main methods of treatment for this disease are as follows: 1. When the number is small, you can use CO2 laser treatment or fractional laser treatment, the efficacy is precise, the traumatic surface is small, generally does not leave scars, you can also freeze treatment, etc.; 2. The effect can be seen in 1 week, and some patients can be cured in 2 weeks, and generally 4 weeks can be cured. Especially the recent increase in skin lesions is obvious, and the color is light red, or a slight itching patients, the effect is better. 3, oral vitamin A acid treatment; 4, wart embedding therapy, or buried wire therapy, acupuncture point injection, etc.