According to WebMD, Botox treatments gradually begin to wear off between four to six months after the injections. Botox paralyzes the muscles into which it is injected, preventing them from contracting and creating wrinkles. As Botox wears off, the muscles regain mobility and wrinkles return.
WebMD states that repeated treatments teach the muscles to stay relaxed and the wrinkles between treatments appear less severe over time. Botox is most frequently used on the face, especially on the forehead, around the eyes and around the mouth. The treatment takes three to seven days to take effect. The site of the injection should not be rubbed for at least 12 hours to prevent the Botox from moving and causing eye drooping.