title: Role of Botulinum Toxin in Depression.
abstract: The goal of this review was to consolidate the evidence concerning the efficacy of botulinum toxin type A (onabotulinumtoxinA) in depression.
  
  
  
  We searched MEDLINE, EMBASE, Cochrane, and Scopus through May 5, 2014, for studies evaluating the efficacy of botulinum toxin A in depression. Only randomized controlled trials were included in the meta-analysis. A pooled mean difference in primary depression score, and pooled odds ratio for response and remission rate with 95% confidence interval (CI) were estimated using the random-effects model. Heterogeneity was assessed using Cochran Q test and χ statistic.
  
  
  
  Of the 639 articles that were initially retrieved, 5 studies enrolling 194 subjects (age 49±9.6 y) were included in the systematic review, and 3 randomized controlled trials enrolling 134 subjects were included in the meta-analysis. The meta-analysis showed a significant decrease in mean primary depression scores among patients who received botulinum toxin A compared with placebo (-9.80; 95% CI, -12.90 to -6.69) with modest heterogeneity between the studies (Cochran Q test, χ=70). Response and remission rates were 8.3 and 4.6 times higher, respectively, among patients receiving botulinum toxin A compared with placebo, with no heterogeneity between the studies. The 2 studies excluded from the meta-analysis also found a significant decrease in primary depression scores in patients after receiving botulinum toxin A. A few subjects had minor side effects, which were similar between the groups receiving botulinum toxin and those receiving placebo.
  
  
  
  This study suggests that botulinum toxin A can produce significant improvement in depressive symptoms and is a safe adjunctive treatment for patients receiving pharmacotherapy for depression. Future trials are needed to evaluate the antidepressant effect per se of botulinum toxin A and to further elucidate the underlying antidepressant mechanism of botulinum toxin A.
authors.affiliation: PARSAIK, HASHMI, JOHN, and OKUSAGA: Department of Psychiatry and Behavioral Sciences, The University of Texas Medical School at Houston, Houston, TXMASCARENHAS: Health Care Management, London Training College, London, UKPROKOP: Mayo Clinic Libraries, Mayo Clinic, Rochester, MNSINGH: Department of Psychiatry and Behavioral Science, University of North Dakota School of Medicine and Health Sciences, Fargo, ND.
authors.forename: Ajay K
authors.initials: AK
authors.lastname: Parsaik
authors.forename: Sonia S
authors.initials: SS
authors.lastname: Mascarenhas
authors.forename: Aqeel
authors.initials: A
authors.lastname: Hashmi
authors.forename: Larry J
authors.initials: LJ
authors.lastname: Prokop
authors.forename: Vineeth
authors.initials: V
authors.lastname: John
authors.forename: Olaoluwa
authors.initials: O
authors.lastname: Okusaga
authors.forename: Balwinder
authors.initials: B
authors.lastname: Singh
mesh_terms: D019274:Botulinum Toxins, Type A / Q000008:administration & dosage / Q000627:therapeutic use*; D003865:Major Depressive Disorder / Q000188:drug therapy*; D006801:Humans; D016032:Randomized Controlled Trials as Topic
chemical_list: D019274:Botulinum Toxins, Type A