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 accept-able 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 = 61) and placebo (saline, n = 27) 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.