Dextromethorphan is Effective for Essential Blepharospasm

Background: Blepharospasm is a focal dystonia presented with continuous involuntary contractions of the muscles surrounding the eyes, causing frequent eyelid closure and visual disturbance. The current treatments for blepharospasm are not very satisfactory. This is a retrospective study of the therapeutic effect of dextromethorphan on blepharospasm. Methods: This retrospective study included 22 patients with essential blepharospasm, who were treated with dextromethorphan. The effect was evaluated using Jankovic Rating Scale (JRS) and Blepharospasm Disability Index (BSDI). Results: Before dextromethorphan treatment, the baseline JRS score is 5.55 ± 1.10 points, and the BSDI score was 2.87 ± 0.59 points. After 1 week of dextromethorphan treatment, the JRS score decreased to 2.82 ± 0.85 points, and the BSDI score decreased to 1.36 ± 0.58 points. In the following 3 weeks of treatment, the JRS and BSDI scores kept in a steady state. One week after the dextromethorphan treatment, the JRS score (5.41 ± 1.01 points) and BSDI score (2.63 ± 0.64 points) returned to the pre-treatment baseline level. Conclusion: We found that dextromethorphan is effective in patients with blepharospasm, and this finding might imply an alternative treatment option to blepharospams.