title: Neurotoxins: Expanding Uses of Neuromodulators in Medicine--Major Depressive Disorder.
abstract: BACKGROUND
  Botulinum toxin A (BTA) is one of the most diversely used medications of the 21st century and is now being researched as a treatment for major depressive disorder (MDD).
  
  
  METHODS
  The authors performed a literature search of PubMed, Web of Science, and the Cochrane Register of Controlled Trials. The primary investigators of the studies were contacted for additional unpublished data.
  
  
  RESULTS
  The authors identified 5 studies that met the criteria of using BTA in the treatment of MDD. All studies showed significant reduction in depressive symptoms with BTA injected into the glabellar muscles. In a pooled analysis, botulinum toxin (n=59) vs placebo (n=75) had a -47% vs -16% reduction in self-rated depression scores (P<0.0001) and a -46% vs -15% reduction in expert-rated depression scores (P<0.0001), respectively. Adverse reactions were mild (temporary headaches and local irritation immediately after injection) and did not differ between active group (13.6%) and placebo group (9.3%) (P=0.44).
  
  
  CONCLUSIONS
  Botulinum toxin injections in the glabellar frown muscles have been associated with a significant improvement in depressive symptoms. Given the prevalence of MDD, the promising results of preliminary trials, and the excellent tolerability of this treatment intervention, larger studies are warranted.
authors.affiliation: Austin, Tex. From the Department of Psychiatry, University of Texas Medical Branch; Department of Psychiatry, Texas A&M Health Science Center; and Department of Dermatology, University of Texas, Dell Medical School.
authors.forename: Michelle
authors.initials: M
authors.lastname: Magid
authors.forename: Brett H
authors.initials: BH
authors.lastname: Keeling
authors.forename: Jason S
authors.initials: JS
authors.lastname: Reichenberg
mesh_terms: D003357:Cosmetic Techniques; D003865:Major Depressive Disorder / Q000188:drug therapy*; D006801:Humans; D009498:Neurotoxins / Q000627:therapeutic use*; D018377:Neurotransmitter Agents / Q000627:therapeutic use*
chemical_list: D009498:Neurotoxins; D018377:Neurotransmitter Agents