These vertical lines that run down from the corners of the mouth to the chin, appear as a result of collagen loss through natural aging of the body. These lines cause the skin to sag and result in a sad or grumpy look for the person.
Neurotoxin injection is found to be an effective treatment for these lines. When it is injected to the DOA muscles that are located underneath these lines and pull down the lips, it relaxes them, thereby reducing the appearance of these lines. For keeping a semi-permanent result, this treatment should be repeated every 3 to 4 months.