title: Recurrent gustatory sweating (Frey syndrome) after intracutaneous injection of botulinum toxin type A: incidence, management, and outcome.
abstract: OBJECTIVE
  To evaluate the duration of effectiveness of intracutaneous injection of botulinum toxin type A for gustatory sweating as well as the incidence, severity, management, and outcome of recurrent gustatory sweating.
  
  
  METHODS
  An inception cohort with a minimum of 18 months of follow-up.
  
  
  METHODS
  A tertiary care center and university teaching hospital.
  
  
  METHODS
  Thirty-three patients with severe gustatory sweating.
  
  
  METHODS
  Intracutaneous injection of 25 to 175 IU (mean, 86 IU) of botulinum toxin type A.
  
  
  METHODS
  Analysis of the effectiveness of the intracutaneous injection of botulinum toxin type A using the Kaplan-Meier actuarial life-table method; completion of the Minor starch-iodine test in patients without symptomatic recurrent gustatory sweating; and the patients' self-assessment of the severity of the recurrent gustatory sweating.
  
  
  RESULTS
  The 1-, 2-, and 3-year actuarial estimate for symptomatic recurrent gustatory sweating was 27%, 63%, and 92%, respectively. In the 7 patients without symptomatic recurrent gustatory sweating, the Minor starch-iodine test revealed persistent gustatory sweating in 6, resulting in an overall 97% rate (32 of 33 patients) for recurrent gustatory sweating. No statistical relationship could be demonstrated between the duration of effectiveness, the incidence of recurrent gustatory sweating, the severity of recurrent gustatory sweating, and the following variables: age, sex, cause of gustatory sweating, skin surface involved, and dose of botulinum toxin type A injection. Within the group of 26 patients with symptomatic recurrent gustatory sweating, (1) the severity of the recurrent gustatory sweating was always reduced when compared with the severity of the initial gustatory sweating, and (2) the recurrent gustatory sweating always remained amenable to reinjection of botulinum toxin type A.
  
  
  CONCLUSIONS
  The present series demonstrated a linear regression in the effectiveness of the intracutaneous injection of botulinum toxin type A in patients with gustatory sweating, while no factors appeared to be statistically related to the duration of effectiveness and/or the incidence of recurrent gustatory sweating. However, because the severity of recurrent gustatory sweating is reduced when compared with the severity of the initial gustatory sweating and because recurrent gustatory sweating remains amenable to reinjection of botulinum toxin type A, we believe that the intracutaneous injection of botulinum toxin type A should become the first-line treatment option in patients with gustatory sweating.
authors: Department of Otorhinolaryngology-Head and Neck Surgery, Hôpital Laënnec, Assistance Publique Hôpitaux de Paris, University Paris V, France.
authors: O
authors: O
authors: Laccourreye
authors: E
authors: E
authors: Akl
authors: R
authors: R
authors: Gutierrez-Fonseca
authors: D
authors: D
authors: Garcia
authors: D
authors: D
authors: Brasnu
authors: B
authors: B
authors: Bonan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D019274:Botulinum Toxins, Type A / Q000008:administration & dosage / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007267:Injections; D008297:Male; D008875:Middle Aged; D009465:Neuromuscular Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D012008:Recurrence; D012189:Retrospective Studies; D013547:Sweating, Gustatory / Q000628:therapy*; D016896:Treatment Outcome
chemical_list: D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A