Injected botulinum toxin enjoys widespread application as a treatment for rhytides caused by excessive contraction of facial muscles. A number of studies have shown that botulinum toxin can be safely and effectively used on the upper face as a way to remove wrinkles (Carruthers A et al. Dermatol Surg 29:461–467, 2003; Carruthers JA et al. J Am Acad Dermatol 46:840–849, 2002; Carruthers JA et al. J Clin Res 7:1–20, 2004). So long as this agent is employed in an appropriate manner, it is rare for complications to occur, and there are no reports indicating either persistent or potentially fatal side effects stemming from its use in aesthetic procedures. With advancing age, rhytides may start to be visible in the frontoglabellar region. If an individual tends to frown a lot, or the muscles in this region are especially active, rhytides tend to appear, even from a young age. The degree of wrinkles correlates with how active the muscles of the upper facial third are. If the frontalis is especially active, rhytides appear in a horizontal orientation. The corrugator supercilii muscle exerts an inferomedial pull on the skin, thus hyperactivity of this muscle results in the formation of wrinkles in an oblique or vertical orientation. Meanwhile, contraction of the procerus draws the glabellofrontal skin downwards, hyperactivity then leading to rhytides overlying the nasal radix and orientated horizontally. As the condition progresses, the muscular fascial covering shrinks and thus wrinkles remain even in the absence of muscular contraction.