What Is Shingles?
Shingles, or herpes zoster, is a painful rash caused by reactivation of the varicella-zoster virus (VZV)—the same virus responsible for chickenpox. After the initial infection, VZV remains dormant in the dorsal root ganglia; reactivation produces a characteristic dermatomal rash.
Common Symptoms
- Prodrome (1–5 days before rash): Burning, tingling, itching, or pain in a specific dermatome; sometimes accompanied by fever, headache, or malaise.
- Rash: Unilateral, dermatomal clusters of vesicles on an erythematous base. The rash evolves through stages: macules → papules → vesicles → pustules → crusts over 7–10 days.
- Pain: Often severe, described as burning, throbbing, or stabbing. Pain may precede the rash by several days.
- Other Symptoms: Fever, chills, fatigue, photophobia, nausea.
Serious Complications
- Postherpetic Neuralgia (PHN): Persistent pain lasting more than 90 days after rash onset; the most common complication, with risk increasing with age.
- Ophthalmic Zoster (V1 trigeminal distribution): Keratitis, uveitis, vision loss—an ophthalmologic emergency.
- Ramsay Hunt Syndrome (CN VII involvement): Facial paralysis, ear pain, vesicles in the ear canal.
- Neurologic Complications: Encephalitis, meningitis, myelitis, stroke (VZV vasculopathy).
- Disseminated Zoster: Widespread rash with visceral involvement (pneumonitis, hepatitis)—primarily in immunocompromised individuals.
- Bacterial Superinfection: Cellulitis, necrotizing fasciitis.
Treatment
- Antivirals (initiate within 72 hours of rash): Valacyclovir 1g TID ×7 days, Famciclovir 500mg TID ×7 days, or Acyclovir 800mg five times daily ×7 days. These reduce severity, duration, and PHN risk.
- Pain Management: NSAIDs, gabapentinoids, tricyclic antidepressants, short-term opioids, topical lidocaine or capsaicin.
- Corticosteroids: Controversial; sometimes used for severe acute pain or cranial nerve involvement alongside antivirals.
Prevention
Shingrix (recombinant zoster vaccine) is over 90% effective and recommended for adults ≥50 and immunocompromised individuals ≥19. Two doses are given 2–6 months apart.
