Canna~Fangled Abstracts

Medical cannabis oil for benign essential blepharospasm: a prospective, randomized controlled pilot study

By January 24, 2022No Comments

doi: 10.1007/s00417-021-05533-1.

Online ahead of print.


Objective: To examine the efficacy and safety of medical cannabis in benign essential blepharospasm (BEB).

Methods: This is a prospective, double-blind, placebo-controlled study. All consecutive adult BEB patients who had been treated with BTX-A injections without success between 3/2019 and 2/2020 were recruited. The study patients were randomly allocated into a treatment and a control (placebo) group in a 1:1 ratio. The treatment group used cannabis drops and the control group used cannabis oil drops during the first 6 weeks of the study, and both groups were treated with the medical cannabis drops during the second 6 weeks. The cannabis dose was gradually increased for each patient depending upon effect and tolerability.

Results: Three patients were included in each group (treatment and control groups). The mean duration of spasm attack during the first 6 weeks was 4.29 min in the treatment group and 73.9 min in the placebo group (P < 0.01). During the last 6 weeks, the treatment group used an average of 6.27 drops and the placebo group used an average of 5.36 drops (P = 0.478). There were 61 spasm events in the treatment group and 94 spasm events in the placebo group (P = 0.05). The mean duration of spasm attack was 1.77 and 8.96 min, respectively (P < 0.01). The side effects were mild, and they included general fatigue, dry mouth, and insomnia.

Conclusions: Medical cannabis can be an effective and safe treatment for BEB as a second line after BTX-A injections when used for 3 months. No significant ocular or systemic side effects was associated with the treatment.

Keywords: Benign essential blepharospasm, Dystonia, Medical cannabis


    1. Elston JS, Marsden CD, Grandas F, Quinn NP (1988) The significance of ophthalmological symptoms in idiopathic blepharospasm. Eye (Lond) 2(Pt 4):435–439 – DOI
    1. Scott AB, Kennedy RA, Stubbs HA (1985) Botulinum A toxin injection as a treatment for blepharospasm. Arch Ophthalmol (Chicago, Ill 1960) 103:347–50 – DOI
    1. Kraft SP, Lang AE (1988) Botulinum toxin injections in the treatment of blepharospasm, hemifacial spasm, and eyelid fasciculations. Can J Neurol Sci 15:276–280 – DOI
    1. Mauriello JA, Dhillon S, Leone T et al (1996) Treatment selections of 239 patients with blepharospasm and Meige syndrome over 11 years. Br J Ophthalmol 80:1073–1076 – DOI
    1. Ben Simon GJ, McCann JD (2005) Benign essential blepharospasm. Int Ophthalmol Clin 45:49–75 – DOI

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