9.4.1.1　Botulinum toxin

Botulinum toxin is safe and effective in the treatment of wrinkles in the upper，middle and lower parts.After 3-7 days of botulinum toxin treatment，muscle paralysis wrinkles will disappear.After 3-6 months，synaptic regeneration will reverse the paralysis（Figure 9-2）.Botulinum toxin is a kind of drug with high safety，and its application in the cosmetic field is relatively safe.However，it needs to be used in accordance with the dose range in the area to optimize patient satisfaction and maintain the natural effect.(https://www.daowen.com)