In the past 20-30 years, cosmetic dermatology has gained a rapid development all over the world. With the continuous improvement of living standards, more and more people are pursuing beauty in form, image and curve to live a beautiful and dashing life. The love of beauty is no longer the patent of young people, but even the elderly people are also dreaming of slowing down the aging process and keeping youth forever, which has become an infinite impetus for the rapid development of “cosmetic skin science”. Nowadays, Botox has been widely used and has become one of the most popular cosmetic methods in the world. Botulinum toxin is a toxin found in food that causes blurred vision, dry mouth, dizziness and nausea, and then muscle relaxation and paralysis after more than half a century of research and clinical use. Botulinum toxin is a purified protein extracted from the bacterium Clostridium botulinum. It is used to treat conditions including nystagmus, spastic squints, spastic dystonia and many other conditions related to muscle dysfunction, including broad neck lines, crow’s feet and hyperhidrosis, and all have been shown to be safe and effective. In addition to the increasing number of cosmetic indications, the therapeutic indications for botulinum toxin are not gradually expanding, such as those that have gone beyond cosmetic, including for headaches and migraines, facial muscle pain, and more. As interest in botulinum toxin has increased, so has knowledge of its functions. Clostridium botulinum produces seven different serotypes of botulinum neurotoxin, all of which act on the neuromuscular junction at the striated muscle fibers and inhibit the release of acetylcholine, resulting in muscle relaxation paralysis. Among the known serotypes, botulinum toxin type A is the most clinically effective. The action of botulinum toxin blocks the nerve conduction to the muscle, so that the muscle does not contract, weakens and relaxes, and the corresponding expression activity produced by its action disappears, for example, the frowning action governed by the interbrow muscle, then the skin wrinkles formed by its action also disappear. Similarly, injections in the bite muscle to achieve the effect of thinning the face in the calf gastrocnemius muscle injection Botox to make the gastrocnemius muscle atrophy thinning, you can get the effect of thinning the legs. Botulinum toxin injection contraindications 1, pregnancy, lactating women. 2, suffering from neuromuscular system diseases such as myasthenia gravis, multiple sclerosis, etc. 3, patients who use aminoglycoside antibiotics. 4.Patients who are very thin and weak. 5, Patients who are allergic to albumin or to botulinum toxin and allergic patients. 6.Patients with severe heart, liver, kidney and lung diseases and patients with connective tissue diseases. Tips for using botulinum toxin 1. The general dose of botulinum toxin for cosmetic use is around 100μ, so it is relatively safe, and even if there are some adverse reactions, they are mostly short-lived and will recover naturally. 2, currently most commonly used in facial wrinkle removal, face slimming, leg slimming, botulinum toxin acts on the motor nerve to muscle conduction, so the injection should find the right location. 3, injection points should be evenly spaced, the distance between about 1.5 cm-2cm, the amount of each point is about 5μ, according to the different locations and role of injection for appropriate adjustment. 4.If there is bleeding during injection, apply pressure for several minutes or apply cold compresses, and stop the injection if there is discomfort. 5.Inject both sides at the same time, the dose and injection point should be the same to avoid asymmetry. 6, according to the process of metabolism and absorption of botulinum toxin in the body, the general interval between the second injection is about 6-9 months. 7.Botulinum toxin injection should be carried out in an environment with rescue measures, just in case.