The use of botulinum toxin A for treatment of possible essential blepharospasm in a dog.

A 3-year-old Great Dane with bilateral possible essential blepharospasm resulting in ocular complications is described. Conservative treatment was not successful and the disease was treated with local injections of botulinum toxin A into the orbicularis oculi muscle. Blepharospasm disappeared completely 5 to 6 days after injection and did not reappear until 3 to 4 months later, at which time the injection was repeated. After several treatments over a period of more than 3 years no side effects have occured. Botulinum toxin A appeared to be effective in the treatment of essential blepharospasm in this dog.