Medical treatment of blepharospasm

Introduction: Blepharospasm is a focal dystonia manifested by repetitive spasms of eyelid muscles, resulting in involuntary eye closure, often accompanied by other facial and neck muscle sustained contractions (cranial–cervical dystonia). Abnormalities in multiple pathways involving the basal ganglia, and aberrant dopaminergic, GABAergic, serotonergic and cholinergic systems have been implicated in blepharospasm and considered as potential targets for pharmacological intervention. Areas covered: Literature was reviewed for relevant case reports, case series, review articles, and update reports on blepharospasm and treatment of blepharospasm including articles on botulinum toxin and other pharmacological interventions. Expert commentary: Botulinum neurotoxin (BoNT) is the first line and mainstay of treatment for blepharospasm. Oral medications for the treatment of blepharospasm may be considered in tardive syndromes, parkinsonian conditions, and as adjunct to BoNT in patients with inadequate symptom control. Dopaminergic agents including levodopa and dopamine agonists, GABAergic agents such as benzodiazepines and baclofen, and anticholinergics such as trihexyphenidyl have been used in patients with blepharospasm with varying benefits. Dopamine-depleting agents including tetrabenazine, deutetrabenazine, and valbenazine have a role in the treatment of secondary blepharospasm due to tardive syndromes.