The discovery of botulinum toxin for wrinkle reduction was an absolutely beautiful accident; in 1986, John Carruther, a professor of ophthalmology at the University of British Columbia (UBC) in Vancouver, Canada, accidentally noticed the disappearance of wrinkles on a patient’s face during an injection of botulinum toxin to treat eye muscle spasms; beginning in 1987, she collaborated with dermatologists on research to introduce botulinum toxin type A In 1987, she collaborated with dermatologists to introduce Botulinum toxin type A into the cosmetic field and was the first to report it in 1992, becoming the founder of Botulinum toxin type A for cosmetic use. The discovery of botulinum toxin was successfully isolated by Van Ermengem in 1897, the natural form of botulinum toxin was obtained by Sommer in 1920, the crystalline form was purified by Schantz in 1946, the mechanism of action was elucidated by Burgen in 1949, and it was used for the treatment of muscle spasms. In late 1979, Schantz’s Botulinum toxin type A was approved by the U.S. Food and Drug Administration (FDA). Currently, there are three similar products in the world: BOTOX from Allergan, Dysport from the UK, and BTXA from China. Botulinum toxin A acts specifically on the presynaptic membrane of the motor nerve end plate, blocking the release of acetylcholine into the synaptic gap, resulting in the inability of the affected nerve to stimulate the contraction of the innervated muscle. It causes a temporary weakening or paralysis of the muscles, resulting in relaxation of the over-contracted muscles of the face and the disappearance of dynamic wrinkles. It does not block the transmission of nerve excitation and there is no excitatory or conductive damage to either nerves or muscles, an effect also known as chemical denervation. The paralyzing effect of botulinum toxin appears 1 to 7 days after injection, reaches its peak in 7 to 14 days, lasts for 12 to 24 weeks, and gradually decreases and disappears with time. In 1973, Scott et al. reported the results of a study of botulinum toxin type A injected into the extraocular muscles of monkeys, confirming that the paralyzing effect of botulinum toxin type A on these muscles could last for 1 to 3 months, and in 1980, Scott et al. reported the use of botulinum toxin type A to treat strabismus in humans. These pioneering studies confirmed that botulinum toxin type A, can be safely and effectively used to treat muscle disorders. In addition to its use for strabismus, Scott et al. began studies on the treatment of dystonia such as blepharospasm, and later expanded to other facial dystonia, spastic squint, and limb dystonia. Even the treatment of muscle function abnormalities, including spastic states, tremor, clonus and sphincter abnormalities, and finally its effect on smooth muscle function abnormalities were studied. John. Carruther, a Canadian ophthalmology professor, began using botulinum toxin type A in 1987 to treat cosmetic problems caused by normally functioning muscles, and made an official report in 1992. The U.S. FDA has allowed botulinum toxin to be used since 1989 for the treatment of strabismus and disorders related to restrictive dystonia over the age of 12. Canada was the first to approve Botulinum toxin type A for cosmetic medical use in 2001, and the U.S. FDA approved Botulinum toxin type A for cosmetic programs to improve moderate to severe frown lines between the eyebrows on April 12, 2002. Since then, as research has progressed, Botox has been used in a variety of fields including ophthalmology, neurology, orthopedics, and plastic and cosmetic surgery. In the field of cosmetic surgery, the main applications are as follows: Initially, Botulinum toxin type A was used to eliminate wrinkles in the upper half of the face, such as horizontal forehead lines, frown lines, crow’s feet, and wrinkles on the back of the nose. Later on, the application was gradually extended to the lower half of the face, such as perioral wrinkles in the elderly, cervical striae deformities, and power folds in the nasolabial folds. Nowadays, besides wrinkle removal, there are also dystonic diseases such as brow asymmetry, facial palsy and spastic slant neck treated with botulinum toxin type A. Through botulinum toxin treatment, the power contrast is adjusted and a coordinated state is achieved. Another scope of application is to adjust muscle volume, which includes bite muscle hypertrophy, lower eyelid orbicularis muscle hypertrophy, facial asymmetry and calf muscle hypertrophy, etc. By paralyzing the nerves that innervate the muscles, the muscles maintain a relaxed state, thus slowly atrophying and achieving the effect of reducing muscle volume. There are also functions such as treating armpit odor by inhibiting the secretion of sweat glands and inhibiting scar growth.