Non-aesthetic uses of botulinum toxin in the head and neck.

INTRODUCTION: The use of botulinum toxin in the specialty of aesthetic surgery in the head and neck is well known. However, it has also been used for other conditions affecting the head and neck, and in recent years its use, as well as the number of relevant applications, has expanded enormously. REVIEW: This article presents a summary of the current range of uses in the laryngeal, pharyngeal, cervical, oromandibular and facial muscles and salivary glands. We highlight particular conditions focusing on dystonia (laryngeal, craniocervical, oromandibular and cervical), multiple system atrophy, migraines, facial nerve palsy, post-laryngectomy, cricopharyngeal dysphagia, Zenker's diverticulum, retrograde cricopharyngeal dysfunction disorder, sialorrhea and gustatory sweating (Frey's syndrome). CONCLUSION: This article should aid the ear, nose and throat surgeon garner knowledge about the range of uses for botulinum toxin in the head and neck.