Definition: Reactivation of the varicella zoster virus (VZV) within sensory ganglia 

  • Simple herpes zoster: lesions in single dermatome without crossing the midline
  • Herpes zoster ophthalmicus: Reactivation of VZV in CN V1 (ophthalmic division).
    • Presents with dermatomal distribution on the face, roughly 50% of cases involve the eye (Liesegang 2008)
  • Disseminated Zoster
    • Rash in multiple dermatomes
    • Rash crosses the midline


  • Affects nearly 1,000,000 people annually in U.S (Yawn 2007)
  • > 30% of the U.S population will experience zoster (Harpaz 2008)
  • 50% of people who live to age 85 will have an episode of Herpes zoster (Schmader 2001)
  • Rates of herpes zoster have been increasing
    • 1949: 0.76 per 1000 person years (Kawai 2016)
    • Estimates as high as 5.2 episodes per 1000 person years in 2007 (Rimland 2010)
  • More prevalent in females, incidence increases with age in both sexes (Kawai 2016)
  • Risk Factors
    • Age
    • Immunocompromised status – including transplant patients, HIV infected patients, and those with underlying malignancy
    • Physical Trauma
    • Chronic lung or kidney disease


  • Reactivation of latent varicella-zoster virus (VZV) in dorsal root ganglia
  • Reactivation of VZV results in inflammation of dorsal spinal ganglia, resulting in dermatomal distribution of pain and vesicular rash

Herpes Zoster (Rosen’s Emergency Medicine)


  • History
    • Previous diagnosis of chickenpox
    • Dermatomal pain and pruritus up to 5 days prior to the development of skin lesions
          • Pain quality may be variable in presentation – aching, burning, or stab-like
  • Physical Exam
    • Rash in dermatomal pattern, typically on trunk
    • Rash is erythematous, typically with a macular base and clear vesicles that progress to scab and crust formation.
      • Formation of scabs takes 10-12 days
      • Heals within 2-4 weeks
        • Other physical exam findings such as lung crackles, hepatomegaly, and neurologic deficits may indicate visceral involvement following cutaneous dissemination

Differential Diagnosis

  • Primary varicella infection
  • Herpes simplex infection
  • Burn
  • Contact Dermatitis
  • Insect bites
  • Impetigo
  • Dermatitis herpetiformis

Management of herpes zoster

  • Disseminated Zoster (Fitzpatrick’s Clinical Dermatology)

    Initiation of antiviral therapy should occur within 72 hours of onset

    • Antiviral therapy
      • Increased rate of healing of skin lesions
      • May reduce acute neuritis
      • May help prevent postherpetic neuralgia
    • If new lesions continue to appear antiviral therapy is recommended, even past 72 hours from onset
    • Choice of antiviral therapy
      • Valaciclovir 1000mg PO Q8 x 7 days
      • Famciclovir 500mg PO Q8 x 7 days
      • Acyclovir 800mg PO five times daily x 7 days
    • Intravenous therapy indicated for
      • Disseminated zoster
      • Zoster ophthalmicus with ocular involvement
      • Inability to tolerate oral medications
  • Analgesia may be needed for the management of acute neuritis
    • First line choices include NSAIDs and acetaminophen
    • For moderate to severe pain, opioid analgesic may be needed
  • Treatment for immunocompromised patient
    • Should be treated regardless of time from onset of lesions
    • If disseminated or involves more than one dermatome IV acyclovir should be used for treatment
  • Patients with active lesions should be counseled to avoid patients who are immunocompromised and pregnant women to avoid transmission

Herpes Zoster Ophthalmicus (Medibes)


  • Postherpetic neuralgia – most common complication and occurs in up to 15% of patients. Incidence increases with age
  • Bacterial skin infection – secondary infection due to open skin lesion
  • Ocular complications, including keratitis and vision loss
  • Disseminated herpes zoster – herpes zoster that is not confined to dorsal root ganglia
    • More common in immunocompromised patients
    • Cutaneous dissemination may progress to visceral organ involvement, resulting in pneumonia, hepatitis, or encephalitis. Visceral dissemination may be life threatening


  • Most patients are suitable for outpatient management with oral antiviral agents and analgesia
  • Indications for admission:
    • Disseminated zoster
    • Immunosuppressed state (HIV, diabetes, chemotherapy)
    • Zoster requiring IV antiviral therapy or analgesic control

Take Home Points

  • Classically, herpes zoster will present with rash and pain in a dermatomal distribution
  • Immunocompromised patients are at greater risk for significant complications of zoster, including visceral dissemination and zoster ophthalmicus
  • Appropriate therapy includes antiviral therapy within 72 hours of onset of symptoms and analgesia for acute neuritis
  • Disseminated zoster and zoster ophthalmicus threatening sight should be treated with IV antivirals

Read More

Emergency Medicine Ireland: Tasty Morsels of EM 073: FRCEM Varicella

Life in the Fast Lane: Herpes zoster ophthalmicus

Up to Date: Treatment of herpes zoster in the immunocompetent host

Concise Review for Clinicians – Herpes Zoster (Shingles) and Postherpetic Neuralgia

Marco CA: Dermatologic Presentations, in Marx JA, Hockberger RS, Walls RM, et al (eds): Rosen’s Emergency Medicine: Concepts and Clinical Practice, ed 8. St. Louis, Mosby, Inc., 2014, (Ch) 110: p 1430-1454.


Liesegang TJ. Herpes zoster ophthalmicus natural history, risk factors, clinical presentation, and morbidity. Ophthalmology. 2008 Feb;115(2 Suppl):S3-12. PMID: 18243930

Yawn BP et al. A population-based study of the incidence and complication rates of herpes zoster before zoster vaccine introduction. Mayo Clin Proc 2007; 82(11): 1341-9. PMID: 17976353

Harpaz R et al. Prevention of herpes zoster: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep. 2008 Jun 6;57(RR-5):1-30; quiz CE2-4. PMID: 18528318

Schmader K. Herpes zoster in older adults. Clin Infect Dis. 2001 May 15;32(10):1481-6. PMID: 11317250

Kawai et al. Increasing incidence of herpes zoster over a 60-year period from a population-based study. Clin Infect Dis. 2016 Jul 15;63(2):221-6. PMID: 27161774

Rimland et al. Increasing incidence of herpes zoster among Veterans. Clin Infect Dis. 2010 Apr 1;50(7):1000-5. PMID: 20178416