Efficacy of botulinum toxin type a after topical anesthesia

Ophthalmic Plast Reconstr Surg. Nov-Dec 2006;22(6):448-52. doi: 10.1097/01.iop.0000248989.33572.3c.

Abstract

Purpose: To determine whether the use of topical anesthesia has an impact on botulinum toxin type A (BTX-A) efficacy.

Methods: Forty patients (20 receiving BTX-A for facial cosmetic rhytid reduction and 20 for benign essential blepharospasm) were evaluated in a double-blind, randomized, triple-crossover study at 2.5- to 4.5-month intervals. The discomfort and efficacy of BTX-A injections after betacaine application to half the face (random assignment) were compared against the discomfort and efficacy of a placebo ointment on the other half of the face. This was followed by cryoanalgesia to the entire face.

Results: Patients ranged from 27 to 81 years of age (mean, 53 years), and 34 were female. Of the 120 total injection comparisons, a better BTX-A effect on one side of the face was reliably identified by 80% and 77% of blepharospasm and cosmetic patients, respectively, with the placebo-treated side providing better BTX-A effect approximately 90% of the time (p < 0.001). Patients reported a more painful side during injection in just 18 of the 120 trials, and only 1 of 40 patients believed the administration of analgesia was worth the trouble.

Conclusions: Pretreatment with topical betacaine followed by skin cooling seems to have a deleterious impact on BTX-A effect without a significantly beneficial patient-perceived reduction in injection discomfort.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Administration, Topical
  • Adult
  • Aged
  • Aged, 80 and over
  • Anesthesia, Local / methods*
  • Anesthetics, Local / administration & dosage*
  • Blepharospasm / drug therapy*
  • Botulinum Toxins, Type A / administration & dosage
  • Botulinum Toxins, Type A / therapeutic use*
  • Cross-Over Studies
  • Double-Blind Method
  • Female
  • Follow-Up Studies
  • Humans
  • Injections
  • Male
  • Middle Aged
  • Neuromuscular Agents / administration & dosage
  • Neuromuscular Agents / therapeutic use*
  • Rhytidoplasty / methods*
  • Treatment Outcome

Substances

  • Anesthetics, Local
  • Neuromuscular Agents
  • Botulinum Toxins, Type A