title: Maximizing extraction of botulinum toxin type A from vials.
abstract: OBJECTIVE
  To determine the residual botulinum toxin remaining in vials after using 3 different extraction methods and to analyze the different techniques for measuring extraction efficacy.
  
  
  METHODS
  Multicentered comparative study.
  
  
  METHODS
  Three academic movement disorder clinics.
  
  
  METHODS
  Thirty physicians were randomly surveyed for their botulinum toxin extraction methods. Three physicians evaluated the most common methods.
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  Amount of toxin left in vials after each extraction method.
  
  
  RESULTS
  Toxin was least successfully extracted by using the vial inversion method. More toxin was extracted by using the 2-in needle method. The top removal method produced the least waste of toxin but is considered unsafe.
  
  
  CONCLUSIONS
  The best and safest method for consistently extracting the most botulinum toxin from its vial was to use a long 21-gauge 2-in needle attached to a 3-mL syringe.
authors.affiliation: Department of Physical Medicine and Rehabilitation, University of Minnesota, Minneapolis, MN 55455, USA. dykst001@maroon.tc.umn.edu
authors.forename: Dennis D
authors.initials: DD
authors.lastname: Dykstra
authors.forename: J Michael
authors.initials: JM
authors.lastname: Wieting
authors.forename: John
authors.initials: J
authors.lastname: McGuire
authors.forename: Thomas
authors.initials: T
authors.lastname: Kowalkowski
mesh_terms: D019274:Botulinum Toxins, Type A / Q000008:administration & dosage*; D004339:Drug Compounding / Q000379:methods / Q000706:statistics & numerical data; D004349:Drug Packaging / Q000379:methods* / Q000706:statistics & numerical data; D006801:Humans; D007273:Injections, Intramuscular / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data; D009339:Needles; D009465:Neuromuscular Agents / Q000008:administration & dosage*; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data; D013396:Suction / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data; D011795:Surveys and Questionnaires; D013594:Syringes; D014481:United States
chemical_list: D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A