A lip flip is a cosmetic procedure that involves injecting a small amount of TOX into the upper lip muscle known as the orbicularis oris. This treatment causes the muscle to relax, which results in a subtle lifting of the upper lip and a more pronounced vermillion border (the line between the lip and skin).

The effect is similar to that of a lip lift surgery, but without the need for incisions or anesthesia. The procedure can be completed in just a few minutes, and the results typically last for 3-4 months.

The lip flip is often used as a complementary treatment to lip filler injections, as it can help to enhance the appearance of the lips and create a more defined cupid's bow. However, it can also be done on its own for those who want a slight improvement in the shape and fullness of their lips without the use of fillers.