Purpose: To establish the efficacy and safety of botulinum toxin in the treatment of Crocodile Tear Syndrome and record any possible complications.
Methods: Four patients with unilateral aberrant VII cranial nerve regeneration following an episode of facial paralysis consented to be included in this study after a comprehensive explanation of the procedure and possible complications was given. On average, an injection of 20 units of botulinum toxin type A (Dysport) was given to the affected lacrimal gland. The effect was assessed with a Schirmer's test during taste stimulation. Careful recording of the duration of the effect and the presence of any local or systemic complications was made.
Results: All patients reported a partial or complete disappearance of the reflex hyperlacrimation following treatment. Schirmer's tests during taste stimulation documented a significant decrease in tear secretion. The onset of effect of the botulinum toxin was typically 24-48 h after the initial injection and lasted 4-5 months. One patient had a mild increase in his preexisting upper lid ptosis, but no other local or systemic side effects were experienced.
Conclusions: The injection of botulinum toxin type A into the affected lacrimal glands of patients with gusto-lacrimal reflex is a simple, effective and safe treatment.