The use of botulinum toxin type A in the treatment of Frey and crocodile tears syndromes

Purpose: We sought to investigate the efficacy of botulinum toxin type A in the treatment of Frey and crocodile tears syndromes. Frey syndrome is a common complication after surgical intervention or injury in the region of the parotid gland. Crocodile tears syndrome is unusual and manifests after facial nerve paralysis and other causes such as head trauma.
Patients and methods: This was a prospective nonrandomized, nonblinded study. We used botulinum toxin type A for the treatment of 11 patients with gustatory sweating and 2 patients with crocodile tears syndrome.
Results: The follow-up (6 to 23 months) of patients with gustatory sweating syndrome showed complete absence of sweating in the affected regions. One patient had recurrence after 16 months and was retreated successfully. At 1 and 24 weeks after treatment of the patients with the crocodile tears syndrome, the Schirmer test showed a reduction of stimulated lacrimation on the impaired side approaching the normal values of the unaffected side.
Conclusions: Our study supports the widely accepted aspect that botulinum toxin type A could be the treatment of choice for gustatory sweating syndrome. We also propose the toxin as a valuable treatment for crocodile tears syndrome.