• Thirty-nine patients with blepharospasm were treated with injections of botulinum A toxin into the lid and brow. The maximum number of injections in one patient was 16 over a period of 24 months. A reduction of abnormal movement occurred in all patients, lasting up to 170 days. Both the amount and the duration of effect were dose dependent. Reinjection for recurrence had effects similar to the original injection. Tearing, dry-eye symptoms, or transient ptosis occurred in 20% of injections, especially in patients who had had previous eyelid surgery.
Scott AB, Kennedy RA, Stubbs HA. Botulinum A Toxin Injection as a Treatment for Blepharospasm. Arch Ophthalmol. 1985;103(3):347-350. doi:10.1001/archopht.1985.01050030043017