Botulinum toxin A (BoNT/A) for the treatment of depression: A randomized, double-blind, placebo, controlled trial in China.

Background: Depression is characterized by low moods, anhedonia, and social avoidance. Effective and acceptable treatments are required for depression. Positive effects on mood have been observed in patients with depression after treatment with botulinum toxin A (BoNT/A).

Methods: A total of 88 patients with depression were randomly assigned to BoNT/A (n = 56) and placebo (saline, n = 22) groups. The primary objective was to determine the change in the 17-item version of the Hamilton Depression Rating Scale (HAMD), 12 weeks after the treatments when compared with the baseline.

Results: The BoNT/A and placebo groups did not differ significantly in all the collected baseline characteristics. However, there was a significant improvement in the depressive symptoms of the BoNT/A group compared to those of the placebo group throughout the 12-week follow-up period. This was according to the measurements of HAMD (F (1, 370) = 9.094, P = 0.0027), Self-rating Depression Scale (SDS) (F (1, 370) = 11.26, P < 0.001), Hamilton Anxiety Scale (HAMA) (F (1, 410) = 8.673, P = 0.0034) and Self-rating Anxiety Scale (SAS) (F (1, 379) = 5.788, P = 0.017). Furthermore, the effectiveness was even higher at the end of the study period.

Limitations: The limitations include the absence of a multicenter study and an inadequate number of cases. Additionally, the mechanism of BoNT/A antidepression was not studied.

Conclusion: This study showed that a single treatment with BoNT/A may accomplish a strong and sustained alleviation of depression in patients.