Pain localized to the dermatome that will be affected by the skin lesions → precedes skin manifestation by 3-5 days.
Rash: erythematous maculopapules affecting one dermatome → maculopapules evolve into vesicles and pustules of various sizes (a distinguishing characteristic from HSV, in which the vesicles are of uniform size) by the 4th day → vesicles subsequently become umbilicated and then form crusts that generally fall off within 3 wk.
Ramsay Hunt syndrome: involvement the trigeminal nerve → painful ear, w/vesicles on the pinna and external auditory canal, facial palsy.Treatment
PO antivirals can ↓ acute pain, inflammation, and vesicle formation when Rx is begun within 72 hr of onset of rash. Rx options are (adjust dose for renal failure):• Valacyclovir 1000 mg × 7 days
• Famciclovir 500 mg tid × 7 days
• Acyclovir 800 mg 5× qd × 7-10 days
Immunocompromised pts: IV acyclovir 10 mg/kg q8h (infusion over 1 hr ) for 7-14 days
Consider adding prednisone in pts >50 yr old within 72 hr of clinical presentation or if new lesions are still appearing. Initial dose is prednisone 40 mg/day ↓ by 5 mg/day until finished. Corticosteroids ↓ in the use of analgesics and time to resumption of usual activities, but there is no effect on the incidence and duration of postherpetic neuralgia.
Postherpetic neuralgia Rx:• Gabapentin 100-600 mg tid
• Lidocaine patch 5% applied to intact skin to cover the most painful area for up to 12 hr within a 24-hr period
Vaccination
Immunocompetent adults ≥50 yr old: single dose of varicella-zoster vaccine (VZV, Zostavax)
Adults who are VZV sero(−) (never had varicella): immunize w/2 doses of varicella vaccine (Varivax).Buy Membership for Internal Medicine Category to continue reading. Learn more here
