Botulinum toxin for the correction of asymmetric crying facies.

The clinical hallmark of asymmetric crying facies (ACF) is a symmetric appearance of the oral aperture and lips at rest, but significant depression of one side of the lower lip with animation (crying or smiling). ACF can resolve spontaneously in the first year of life, but surgical intervention may be required at some point to ensure a good cosmetic outcome. The authors report on the successful use of botulinum toxin type A to achieve temporary facial symmetry in two children with ACF with results lasting up to six months and suggest that such treatments may be helpful in providing more time to consider and/or plan surgical intervention.