Amitriptyline: An effective intervention in Post-herpetic neuralgia prevention? Evidence from a randomized control trial
Keywords:
Amitriptyline, Herpes zoster, Post Herpetic NeuralgiaAbstract
Background Postherpetic neuralgia (PHN) is a chronic painful condition of neuronal origin lasting more than 3 months in the previously involved dermatome by herpes zoster. PHN remains the most common and debilitating complication of herpes zoster affecting the quality of life of such patients. A variety of symptoms have been reported including pain, allodynia, hyperalgesia, paresthesia, and dysesthesia, in the absence of active herpes lesions. Although there are several therapeutic options for PHN, there is little information available regarding its prevention. This study aimed to fill this research gap and explore the role of amitriptyline in preventing PHN. Objective To evaluate the efficacy of Amitriptyline in the prevention of Post Herpetic Neuralgia (PHN). Methods A total of 120 herpes zoster patients, presenting within 3 days were selected. Patients were split into two groups. Group A received 25 mg amitriptyline along with famciclovir, while group B used only oral famciclovir. Both groups were given other analgesics like Gabapentin, topical analgesics, and NSAIDs on a need basis. Patients were evaluated at monthly intervals and the final pain scores were calculated after 3 months. Results At the baseline, patients in the significant pain category were comparable in both groups. After 3 months the number of such patients in Group B was higher. Similarly, there was clear disparity between the two groups regarding the number of patients achieving good/ excellent pain reduction (p valve<0.05). Conclusion This study showed that oral Amitriptyline started concomitantly with antivirals significantly reduced the incidence of post-herpetic neuralgia.References
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