Title: Efficacy of Cryoanalgesia versus Systemic Gabapentin in the Treatment of Post Herpetic Neuralgia: A Randomised Control Trial
Authors: Balkrishna P Nikam, Varsha P Jamale, Amitoj Garg, Mohan S Kale, Dhanraj D Chavan
DOI: https://dx.doi.org/10.18535/jmscr/v6i7.29
Abstract
Introduction: PHN is defined as pain persisting for more than 4 weeks after the rash has healed. Despite increasing understanding of pathophysiology and advances in therapy the quest for the penultimate therapy for PHN still remains elusive. Out of various treatment options available anticonvulsants or tricyclic-antidepressants drugs are preferred. Cryoanalgesia is routinely used in interventional pain management settings. Recently it has been successfully used in treating PHN by Calandria L.
Material & Methods: 50 Patients of PHN on daily oral amitriptyline (25mg) were randomly divided into two groups of 25 each; group ‘A’ received weekly cryoanalgesia {60-90 seconds by non-freezing cryo (liquid nitrogen) spray} and group ‘B’ received daily oral gabapentin (600mg) for 8 weeks. Efficacy was studied by a blinded investigator using visual analogue score (VAS), SF- McGill pain questionnaire (Sf-MGPQ). Safety was studied by appropriate investigations.
Results: Baseline mean VAS and Sf-MGPQ of group A and B were 100& 0.90 and 100& 0.90 respectively. At the end of 8 weeks mean VAS and Sf-MGPQ of group A and B were reduced to 14& 0.13 and10.4& 0.07 respectively. The difference in both the groups was not statistically significant (P=0.39)
Conclusion: Combination of cryoanalgesia and amitriptyline is well tolerated and its efficacy is equivalent to conventional therapy of gabapentin and amitriptyline.
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