Contralateral injections of botulinum A toxin for the treatment of hemifacial spasm to achieve increased facial symmetry.

Six patients noted facial asymmetry after botulinum toxin injection for hemifacial spasm. Each patient was injected on the side contralateral to the spasms with 10 to 15 IU over the zygomatic major and minor muscles. Each patient noted improvement in facial symmetry in the resting position and dynamic facial movements. Five of the six patients desired this approach with subsequent injections. This injection method variation proved helpful in the managing of hemifacial weakness created by botulinum A toxin for this condition.