Cannabidiol as an Adjunct to Botulinum Toxin in Blepharospasm - A Randomized Pilot Study

Area of Science:

• Neurology
• Pharmacology
• Ophthalmology

Background:

• Blepharospasm (BPS) is a focal dystonia causing involuntary eyelid spasms.
• Idiopathic adult-onset BPS often requires ongoing treatment for symptom control.
• Current treatments like botulinum toxin (BTX) may not fully manage breakthrough symptoms.

Purpose of the Study:

• To evaluate the safety and efficacy of low-dose cannabidiol (CBD) as an add-on therapy for adult-onset blepharospasm (BPS).
• To develop and validate a novel objective methodology for assessing BPS treatment response.
• To investigate CBD's impact on eyelid kinematics and clinical symptom severity.

Main Methods:

• A 6-month, prospective, randomized, double-masked, placebo-controlled crossover study.
• 12 patients with BPS receiving standard BTX therapy were enrolled.
• Eyelid kinematics were quantified via video analysis, and the Jankovic Rating Scale (JRS) was used for clinical assessment.

Main Results:

• Low-dose CBD was well-tolerated, with no adverse events reported.
• CBD significantly improved objective kinematic measures: decreased eyelid closure amplitude and duration, and increased closure velocity.
• The JRS indicated a trend towards improvement, but this did not reach statistical significance.

Conclusions:

• Low-dose CBD demonstrates a safe and effective adjunctive treatment profile for blepharospasm (BPS).
• Objective kinematic improvements suggest CBD's therapeutic potential in managing BPS.
• Further research is warranted to confirm clinical significance and optimize treatment protocols.