Using a very fine needle, a tiny amount of toxin is injected into the muscles of the face. The toxin works by blocking nerve signals to the muscles, preventing them from contracting, which can temporarily relax the targeted muscles. As the muscles relax,  dynamic lines and wrinkles can no longer move, resulting in a smoother, wrinkle free appearance.   The effects are temporary, usually lasting several months, and treatments may need to be repeated to maintain the results.