Herpes Zoster (Shingles)
Etiology Varicellar Zoster
Transmission activation of latent virus
Clinical symptoms Radicular pain with vesicular eruptions. T5-T10 most commonly affected, 2nd most common: V1
Treatment with antiviral agent, start treatment as early as possible
  • Famciclovir (Famvir): 500 mg orally three times daily for 7 days, cost about $140
  • Valacyclovir (Valtrex): 1 g orally three times daily for 7 days, cost about $80
  • Prednisone (Deltasone) 30 mg orally twice daily on days 1 through 7; then 15 mg twice daily on days 8 through 14; then 7.5 mg twice daily on days 15 through 21 2 (2 to 4) for days 1 through 7, 2 (1 to 3) for days 8 through 14, 1 (1 to 2) for days 15 to 21
  • May shorten disease, prevent postherpetic neuralgia
  • Immunocompromised, multiple dermatome involved or severely ill: consider IV Acyclovir 10mg/kg q8 X 7 days.
Ophthalmic Zoster
  • may cause keratoconjunctivitis or iridocyclitis, cerebral vasculitis
Post herpetic Neuralgia
  • 9% of patient has pain persist > 4 weeks
  • Half of them will resolve in 8 weeks
  • < 2% persist > 2 years
  • rare for patients < 50 yo
Treatment of post herpetic neuralgia
  • Tricyclics: Elavil 10 mg/ day, gradually increase dose
  • Carbamazepine: 200 mg bid, titrate up
  • Neurontin 400 mg q8, titrate up
  • Pimozide 4-12 mg/day in refractory case
References & further reading