Successful treatment of crocodile tears by injection of botulinum toxin into the lacrimal gland: A case report

Pathologic lacrimation (crocodile tears) is a rare but stigmatizing symptom after facial nerve paralysis. The aim of this pilot study was to examine whether botulinum toxin injection into the lacrimal gland is effective in reducing pathologic tear secretion. Case report. One patient who had crocodile tears after a zoster oticus infection received a botulinum toxin injection (2.5 mouse units) into the lacrimal gland. Before injection, 1 week, 1 month, and 6 months after injection, patient’s lacrimation was assessed by a Schirmer test. The lacrimation of the injected eye was reduced after 1 week and equal after 1 month when compared to the healthy side. After 6 months, hyperlacrimation reoccurred. No side effects were observed. Intraglandular injection of botulinum toxin into the lacrimal gland may serve as a sufficient therapy for crocodile tears.