title: Sterility assessment of multiple use botulinum A exotoxin vials: a prospective simulation.
abstract: BACKGROUND
  A preponderance of evidence now indicates that storage of reconstituted botulinum toxin solution for longer than the 4 hours recommended by the manufacturer does not result in loss of effectiveness.
  
  
  OBJECTIVE
  Then purpose of this study was to assess whether serial re-extraction of reconstituted botulinum toxin solution from vials undergoing prolonged storage is associated with increased risk of microbial contamination.
  
  
  METHODS
  Consecutive 100-U vials of botulinun A exotoxin were reconstituted with 2.5 mL each of normal saline with preservative (benzyl alcohol). Within 1 week after reconstitution, each vial was used to treat 1 to 3 patients, for a total of 60 to 80 U used. Thereafter, each vial was stored in a plastic kidney basin in an unlocked, multiuse medication refrigerator. Two weeks later, a randomly assigned nurse removed the vial from the refrigerator and withdrew and discarded 0.1 mL (5 U) using the same technique used for therapeutic extractions. Iterations of this withdrawal and discarding procedure were continued until a 0.1-mL aliquot could not be withdrawn without prying off the metal cover. Once this threshold was reached, the vial was sent to the microbiology laboratory for sterility testing using a thioglycolate broth.
  
  
  RESULTS
  In all, 127 vials were handled per protocol. On average (mean), vials underwent 4.5 access procedures, including 1.6 therapeutic extractions for a total of 76 U removed during a period of 7 weeks. Sterility analysis with thioglycolate broth indicated no evidence of contamination.
  
  
  CONCLUSIONS
  Preservative-containing saline was used for reconstitution.
  
  
  CONCLUSIONS
  Routine refrigerator storage of medication vials containing reconstituted botulinum toxin does not result in microbial contamination of the contents even after serial re-extraction of solution from these vials, and after handling of such vials by multiple personnel. Storage and subsequent reuse of botulinum toxin appears safe for at least 7 weeks after reconstitution.
authors.affiliation: Section of Cutaneous and Aesthetic Surgery, Department of Dermatology, Northwestern University, Chicago, IL 60611, USA. m-alam@northwestern.edu
authors.forename: Murad
authors.initials: M
authors.lastname: Alam
authors.forename: Simon S
authors.initials: SS
authors.lastname: Yoo
authors.forename: David A
authors.initials: DA
authors.lastname: Wrone
authors.forename: Lucile E
authors.initials: LE
authors.lastname: White
authors.forename: John Y S
authors.initials: JY
authors.lastname: Kim
mesh_terms: D019274:Botulinum Toxins, Type A / Q000592:standards*; D004340:Drug Contamination; D004349:Drug Packaging; D004356:Drug Storage; D006801:Humans; D009465:Neuromuscular Agents / Q000592:standards*; D011446:Prospective Studies; D011897:Random Allocation; D012034:Refrigeration; D012307:Risk Factors; D013242:Sterilization; D013997:Time Factors
chemical_list: D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A