Comparative effectiveness of two different doses of botulinum toxin A for the treatment of mild to moderate depression.

[OBJECTIVE] Botulinum toxin A has been shown to be effective in managing depression. This study aimed to evaluate the antidepressant and antianxiety effects of two different doses of botulinum toxin A in patients with mild to moderate depression.

[METHODS] A total of 140 patients diagnosed with mild to moderate depression at the Department of Neurology of the Second Affiliated Hospital of Soochow University from September 2020 to September 2021 were enrolled for the study. The patients were allocated into two groups and treated with two different doses of botulinum toxin A (50 units or 100 units). Depression scores (HAMD, HAMA, SDS, and SAS) were evaluated at baseline and 1, 2, 4, 8, and 12 weeks after treatment.

[RESULTS] There was a significant improvement in the depressive and anxiety symptoms following treatment with the botulinum toxin A after 12 weeks compared to the baseline. However, there were no significant differences between the two groups. Further, the factor scores of anxiety/somatization, blocking, sleep disorder, and cognitive disorder were significantly decreased after 12 weeks of treatment with 50 units of botulinum toxin A compared to the baseline (P < 0.05). Further, the factor scores of somatic and mental anxiety were significantly decreased at different time points after treatment with 50 units of botulinum toxin A compared to the baseline (P < 0.05).

[CONCLUSION] Local injections of 50 units and 100 units of botulinum toxin A shows equal efficacy. Therefore, 50 units of botulinum toxin A could be used clinically to manage mild to moderate depression.