Big difference. Botulinum toxin injections reduce wrinkles by weakening or paralyzing the muscles that cause the wrinkles (no frowning=no frown lines). The brow lift is a surgical procedure that reduces the forehead creases and lifts the brows to create a younger look. It is a more extensive procedure than botulinum toxin injections.
Forever vs 4 months. Brow lift is a surgical procedure which resets the brows at a more youthful level; it also helps smooth the forehead. Botox is a medical treatment that can elevate the brow slightly but definitely smooths the forehead. The effects of brow lifts last many years, while botox's effects last 3-4 months, on average. Not all patients are candidates for either, so check with a facial plastic surgeon.