EPIDEMIOLOGICAL CHARACTERISTICS OF PATIENTS WITH POSTHERPETIC NEURALGIA TREATED WITH BOTULINUM TOXIN
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Abstract
Background: Postherpetic neuralgia is a common complication of Herpes zoster, causing persistent pain and significantly affecting quality of life. Current medical treatments remain limited due to adverse effects associated with long-term use. Botulinum toxin type A is considered a potential therapeutic option.
Objective: To investigate the epidemiological characteristics of patients with postherpetic neuralgia treated with botulinum toxin.
Methods: A case series study was conducted on 10 patients aged ≥18 years with postherpetic neuralgia lasting ≥3 months at Ho Chi Minh City Hospital of Dermato-Venereology (February-October 2025). Patients received BoNT-A injections with a mean dose of 75 units and an average of 15.3 injection points. Pain intensity was assessed using the Visual Analog Scale (VAS) at baseline, 2 weeks, 1 month, and 3 months after treatment. Epidemiological characteristics were also recorded.
Results: The mean age was 69.3 years (range 47-83), with the majority aged ≥60 years; 60% were male and 40% female. The mean duration of pain was 3 months. The most commonly affected areas were the trunk (70%) and face (30%). The baseline VAS score was 9.4 ± 0.70.
After treatment, the VAS score decreased to 2.7 ± 0.95 at 2 weeks, 2.5 ± 0.97 at 1 month, and 3.1 ± 0.74 at 3 months (p < 0.0001), corresponding to an average reduction of 67.3%. The pain area decreased from 100% at baseline to 29 ± 15.2% after the first assessment, remained at 29 ± 15.2% after the second, and increased slightly to 36 ± 17.0% after the third (p < 0.0001). No significant correlation was found between age and treatment efficacy, nor between dosage and reduction in pain area (p > 0.05).
Conclusion: Botulinum toxin type A is an effective and safe treatment for postherpetic neuralgia. Epidemiological factors such as age, injection dose, and pain area showed no correlation with treatment outcomes.
Keywords
Postherpetic neuralgia, Botulinum toxin type A
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References
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