Viral Dermatology • ICD-11: 1E91

Herpes Zoster (Shingles): VZV Reactivation, Dermatomal Distribution & Early Antiviral Protocols

Author: Mallikarjun R (Founder) & Medicus Labs Medical Team • Review: 12 min read • ✓ Peer-Referenced

1. Neuropathology of VZV Reactivation

Herpes Zoster occurs when latent Varicella Zoster Virus (VZV) reactivates within sensory dorsal root or cranial nerve ganglia, traveling down the axon to produce a unilateral, dermatomal eruption of grouped erythematous papules and vesicles accompanied by severe neuropathic pain.

2. The Critical 72-Hour Therapeutic Window

Administering oral Valacyclovir (1000mg TID) or Famciclovir (500mg TID) within 72 hours of rash onset substantially accelerates cutaneous healing and decreases the incidence of debilitating Post-Herpetic Neuralgia (PHN).