Botox is a protein. This protein actively binds to and deactivates a specific type of nerve, the ones that control voluntary muscles, sweat glands, and saliva glands. The "toxin" description is only in the event that the deactivated nerves are important to life function, like breathing for example. Typical volumes of Botox injected into the face for cosmetic purposes are too small to have any impact on any "life function". . .by a lot.
Botox protein is "digested" by the body naturally over a few months. It has never been shown to do anything except as noted above and has been in use for more than 20 years. The most dangerous part of coming to my office for a Botox injection, is the drive to the office. . . again, by a lot.