A, laser hair removal can solve the problem —- indications armpit hair, forearm hairy, calf hairy, upper lip hairy, hairy between the eyebrows (even heart eyebrows), sideburns hairy (sideburns down), jaw hairy. Hairy areola, hairy forehead, hairy lower abdomen, perineal area (bikini), hairy posterior waist area. Hairline advancement, etc. Pseudofolliculitis in the beard. Second, the adverse reactions and risks of laser hair removal intraoperative, postoperative pain, edema, erythema around the hair follicle. Epidermal injury, recurrence of herpes simplex, folliculitis, hyperpigmentation, hypopigmentation, loss. Scarring. Disappearance of freckles, tattooing or pigmented damage reduction. Postoperative reticular cyanosis, pruritus, urticaria. Paradoxical hair growth. Contraindications and precautions 1, the local skin with active infection is prohibited. 2. Use with caution in cases of severe cardiopulmonary, hepatic and renal diseases and infectious diseases. 3. Contraindicated for pregnant and lactating women, and caution for menstruating women. 4. Forbidden within 6 months of oral treatment with retinoic acid. 5. Use with caution or forbidden for those with scar. 6. Use with caution if you have a history of recurrent staphylococcal or herpes simplex virus infections, or take oral medication to prevent infection if needed. 7, vitiligo patients with psoriasis patients caution or prohibited. 8, oral phenytoin sodium, cyclosporine, immunosuppressants, hormone therapy and other drugs, suffering from late-onset dermal porphyria, thyroid disease, metastatic tumor, malnutrition disease or anorexia nervosa, polycystic ovary syndrome, etc., hirsutism may be affected by it, laser treatment may not be effective. IV. Mechanism and requirements Selective photothermal theory and the fine anatomical structure and physiological changes of the hair follicle department are the premise that laser hair removal can be effective for a long time or even individually can achieve permanent hair removal. Special wavelength laser, such as 800nm semiconductor laser, can penetrate the skin to a certain depth (dermis) to reach the treatment depth (the longer the wavelength the deeper the penetration depth), the melanin in the hair follicle can absorb some specific wavelength photon energy to produce thermal changes for the laser to destroy the hair follicle becomes possible (other tissue components in the dermis do not absorb these wavelengths of laser energy). The other thing to consider is the balance between how much energy can destroy the hair follicle and how much energy can be used to make the melanin in the epidermis not have destructive consequences (melanin in the epidermis is an important interfering factor, which is expressed in the skin color), i.e. how to remove hair effectively without complications. This balance requires the patient’s objective conditions, the operator’s professional medical knowledge and clinical experience, as well as strict preoperative and postoperative care to achieve. The color and thickness of the hair to be removed and the skin type of the patient determine the efficacy and complications to a certain extent. Five, the advantages and disadvantages of laser hair removal 1, the advantages, the effect is relatively the most lasting, and can even achieve the so-called permanent hair removal. Each time the speed of treatment is faster, in the treatment of large areas of hair area at this stage any treatment can not be compared with the laser. Generally a course of 5-7 times treatment, can make a significant reduction in hair, about 80% can achieve permanent hair removal. Relatively non-invasive and fast recovery. The most ideal patients for laser hair removal are: fair skin, thick and black hair in the area to be treated, and normal endocrine level. 2.Disadvantages: slightly expensive. There is tolerable but mild to moderate pain during the treatment. White or light-colored hair is not effective, the effect of slender hair is poor, the course of treatment is longer. The area around the eyes can not be treated. Although laser is the best and most definitive treatment available, it is still not possible to achieve no hair left. Any laser treatment requires pre-treatment, mid-treatment and post-treatment sun care. VI. Precautions before and after treatment 1. Sun protection for 4 months before treatment (SPF>15) or no history of sun exposure or tanning within 4 months. If you have a recent history of sunbathing or sun exposure in the highlands or wilderness, it is recommended to withhold treatment and / or use topical decolorizers until the skin tone is restored. 2.Do not pluck or wax the hair before treatment until the day of treatment clean the surgical area and scrape out the hair. 3.Clean the operation area before treatment, remove residual cosmetics and skin care products. If necessary, topical lidocaine gel can be used before treatment to relieve pain. 4.Cold compresses after treatment can reduce pain and the chance of postoperative blisters. Avoid contact with hot water, bathing, swimming, strenuous exercise and alcohol consumption within 24 days after treatment. Avoid any damage to the treatment area (e.g. scratching). 5. Pay attention to sun protection (SPF>30) during the treatment course and 3 months after the treatment. 6, 1 week to a few weeks after the operation of the damaged hair stumps will be excluded from shedding, not hair regeneration phenomenon, no need to panic. Treatment interval is mostly 1 month to one and a half months. However, when hair regrowth is found, you can follow up with the clinic again. The efficacy of hair removal can be summarized as follows: the absolute number of hairs is reduced (permanently), the regenerated hairs are finer and less obvious in color, and the growth of hairs is delayed (within a few months). VIII. Treatment process: ①Take medical history in order to select suitable treatment subjects. ② Conduct a physical examination to assess skin color, skin condition, hair color, hair diameter, and hair density. ③Instruct the patient on preoperative preparation and skin care. ④Determine the treatment plan according to the nature of the skin and hair. ⑤ Provide appropriate post-operative protection.