What is the recommended management for a patient presenting with herpes zoster?

Management of Herpes Zoster

First-Line Treatment for Uncomplicated Herpes Zoster

For uncomplicated herpes zoster, initiate oral valacyclovir 1 gram three times daily for 7 days as first-line therapy, ideally within 72 hours of rash onset. 1

Alternative Oral Antiviral Options

• Acyclovir 800 mg orally five times daily for 7 days is an effective alternative, though the dosing schedule is less convenient than valacyclovir or famciclovir 1, 2
• Famciclovir 500 mg three times daily for 7 days offers comparable efficacy with better bioavailability and more convenient dosing than acyclovir 3, 4
• All three agents (valacyclovir, famciclovir, acyclovir) are well-tolerated and do not differ significantly in efficacy or safety 5

Critical Timing Considerations

• Treatment must be initiated within 72 hours of rash onset to maximize effectiveness in reducing severity, duration of acute pain, and preventing complications 1, 6
• Delayed initiation beyond 72 hours significantly reduces treatment effectiveness 1
• However, all immunocompromised patients require antiviral treatment regardless of timing 1

Severe or Complicated Disease Requiring IV Therapy

Switch to intravenous acyclovir 5-10 mg/kg every 8 hours for:

• Disseminated herpes zoster (multi-dermatomal involvement) 1, 2
• Ophthalmic zoster (requires urgent ophthalmology referral due to risk of vision-threatening complications) 1, 7
• Visceral involvement 1
• Any herpes zoster in severely immunocompromised patients 1, 2
• Patients requiring hospitalization 1

Duration and Transition Strategy

• Continue IV therapy until clinical improvement occurs, then switch to oral therapy to complete the treatment course 1
• Treatment should continue for a minimum of 7-10 days and until clinical resolution is attained (all lesions have scabbed) 1, 2
• If new lesions continue to form or healing is incomplete, extend treatment beyond 7 days 1

Management in Immunocompromised Patients

Immunocompromised patients require special considerations:

• Initiate antiviral therapy regardless of timing from rash onset 1
• Temporarily reduce or discontinue immunosuppressive medications in severe cases of disseminated VZV infection 1, 2
• Immunosuppression may be restarted after commencing anti-VZV therapy and after skin vesicles have resolved 1
• Monitor closely for dissemination and visceral complications 1
• Consider longer treatment duration if healing is delayed 1
• Laboratory confirmation with PCR is needed for atypical presentations 2, 5

Acyclovir-Resistant Cases

For suspected acyclovir-resistant herpes zoster (rare, typically in severely immunocompromised patients):

• Foscarnet 40 mg/kg IV every 8 hours is the treatment of choice 1
• Acyclovir-resistant isolates are routinely resistant to ganciclovir as well 1
• Desensitization to acyclovir may be considered in consultation with an allergy specialist for patients with adverse reactions to both valacyclovir and acyclovir 1

Pain Management

Acute pain control is a critical treatment goal:

• Appropriately dosed analgesics should be initiated alongside antiviral therapy 5
• Consider adding a neuroactive agent such as amitriptyline for neuropathic pain 5
• For postherpetic neuralgia (pain persisting >90 days), use gabapentin, pregabalin, or tricyclic antidepressants 4, 6
• Topical lidocaine patches or capsaicin cream may provide additional relief 7, 6

Prevention Strategies

Vaccination is the most effective prevention strategy:

• Recombinant zoster vaccine (Shingrix) is recommended for all adults aged 50 years and older, regardless of prior herpes zoster episodes 1, 2
• Vaccination should ideally occur before initiating immunosuppressive therapies 2
• The vaccine significantly reduces the incidence of both herpes zoster and postherpetic neuralgia 4, 6

Post-Exposure Prophylaxis

For varicella-susceptible patients exposed to active varicella zoster infection:

• Varicella zoster immunoglobulin within 96 hours of exposure is recommended 1, 2
• If immunoglobulin is unavailable or >96 hours have passed, give a 7-day course of oral acyclovir beginning 7-10 days after exposure 1, 2

Common Pitfalls to Avoid

• Do not use topical antiviral therapy alone—it is substantially less effective than systemic therapy and is not recommended 2
• Do not delay treatment waiting for laboratory confirmation in typical presentations—diagnosis is primarily clinical 5
• Do not withhold treatment in immunocompromised patients even if presenting beyond 72 hours 1
• Facial zoster requires particular attention due to risk of cranial nerve complications and should prompt consideration of ophthalmology consultation 2