Postherpetic Neuralgia

The incidence and prevalence of PHN vary markedly across geographic regions and demographic groups, driven by ageing demographics, regional disparities in vaccination coverage, differences in healthcare access, and genetic susceptibility. Postherpetic neuralgia is defined as pain persisting more than 90 days after herpes zoster rash onset. PHN pain can manifest as shooting, burning, sharp, stabbing, or electric shock-like sensations and may persist for months to years. PHN severely impairs psychosocial function, disrupts sleep, daily activities, and work capacity, and causes significant psychological distress and increased healthcare utilisation.