What is the recommended treatment for a patient with herpes zoster (shingles)?

Treatment of Shingles (Herpes Zoster)

For uncomplicated shingles in immunocompetent adults, initiate oral valacyclovir 1000 mg three times daily for 7 days, starting within 72 hours of rash onset, and continue treatment until all lesions have completely scabbed. 1, 2

First-Line Antiviral Therapy

Oral antiviral therapy is the cornerstone of shingles treatment and should be initiated as soon as possible after diagnosis. 1, 2

Standard Dosing Regimens for Uncomplicated Disease

• Valacyclovir 1000 mg orally three times daily for 7 days is the preferred first-line treatment due to superior bioavailability and convenient dosing 1, 2
• Famciclovir 500 mg orally three times daily for 7 days is equally effective and offers better adherence than acyclovir 1, 3, 4
• Acyclovir 800 mg orally five times daily for 7-10 days remains effective but requires more frequent dosing 1, 2, 5

Critical Timing Considerations

• Treatment is most effective when initiated within 48 hours of rash onset, but the 72-hour window is the maximum timeframe for optimal efficacy 1
• Treatment should NOT be withheld if presenting beyond 72 hours, as evidence suggests valacyclovir may still provide benefit when started later 6
• Continue antiviral therapy until all lesions have completely scabbed, not just for an arbitrary 7-day period 1, 2

Treatment Algorithm Based on Disease Severity

Uncomplicated Herpes Zoster (Single Dermatome, Immunocompetent)

• Valacyclovir 1000 mg three times daily for 7 days OR 2
• Famciclovir 500 mg three times daily for 7 days OR 3
• Acyclovir 800 mg five times daily for 7-10 days 2
• Continue until all lesions have scabbed 1, 2

Disseminated or Invasive Herpes Zoster

Switch to intravenous acyclovir 5-10 mg/kg every 8 hours for disseminated disease (multi-dermatomal, visceral involvement, or CNS complications). 1, 2

• Continue IV therapy for a minimum of 7-10 days and until clinical resolution is attained 1, 2
• Switch to oral therapy once clinical improvement occurs 2
• Consider temporary reduction in immunosuppressive medications if applicable 1, 2

Immunocompromised Patients

• All immunocompromised patients with herpes zoster require antiviral treatment regardless of timing 2
• For uncomplicated disease: oral valacyclovir or famciclovir at standard doses 1
• For disseminated or severe disease: intravenous acyclovir 10 mg/kg every 8 hours 1
• Consider longer treatment duration if healing is delayed 2
• Monitor closely for dissemination and visceral complications 2

Facial/Ophthalmic Herpes Zoster

• Initiate oral valacyclovir 1000 mg three times daily or famciclovir 500 mg three times daily with particular urgency given risk of ophthalmic and cranial nerve complications 1
• Escalate to IV acyclovir for complicated facial zoster with suspected CNS involvement or severe ophthalmic disease 1
• Elevation of the affected area to promote drainage and keeping skin well hydrated with emollients is recommended 1

Special Populations and Dosing Adjustments

Renal Impairment

Dose adjustments are mandatory to prevent acute renal failure in patients with renal impairment. 1, 3

• For famciclovir in herpes zoster with CrCl ≥40 mL/min: 500 mg every 8 hours 3
• For CrCl 20-39 mL/min: 500 mg every 12 hours 3
• For CrCl <20 mL/min: 500 mg every 24 hours 3
• For hemodialysis: 250 mg following each dialysis 3
• Monitor renal function closely during IV acyclovir therapy 1

HIV-Infected Patients

• Famciclovir 500 mg twice daily for 7 days for recurrent orolabial or genital herpes 3
• Higher oral doses (up to 800 mg 5-6 times daily) may be needed for herpes zoster 1
• Consider long-term acyclovir prophylaxis (400 mg 2-3 times daily) for frequent recurrences 1

Acyclovir-Resistant Cases

For proven or suspected acyclovir-resistant herpes zoster, switch to foscarnet 40 mg/kg IV every 8 hours until clinical resolution. 1, 2

• All acyclovir-resistant strains are also resistant to valacyclovir, and most are resistant to famciclovir 1
• Resistance is extremely rare in immunocompetent patients but occurs more frequently in immunocompromised patients receiving prolonged suppressive therapy 1
• If lesions fail to begin resolving within 7-10 days, suspect acyclovir resistance and obtain viral culture with susceptibility testing 1

Adjunctive Therapies and What to Avoid

Corticosteroids

• Prednisone may be used as adjunctive therapy in select cases of severe, widespread shingles but carries significant risks, particularly in elderly patients 1
• Prednisone should generally be avoided in immunocompromised patients due to increased risk of disseminated infection 1
• A 21-day course of acyclovir with prednisolone confers only slight benefits over standard 7-day acyclovir treatment and does not reduce postherpetic neuralgia 5

Therapies NOT Recommended

• Topical antiviral therapy is substantially less effective than systemic therapy and is not recommended 1, 7
• Topical anesthetics provide minimal benefit and are not recommended as primary therapy 1

Infection Control and Prevention

Isolation Precautions

• Patients with shingles should avoid contact with susceptible individuals until all lesions have crusted, as lesions are contagious to individuals who have not had chickenpox 1
• Cover lesions with clothing or dressings to minimize transmission risk 1
• For disseminated zoster (lesions in >3 dermatomes), implement both airborne and contact precautions 1

Post-Exposure Prophylaxis

• Varicella zoster immunoglobulin (VZIG) within 96 hours of exposure is recommended for varicella-susceptible patients exposed to active infection 1, 2
• If immunoglobulin is unavailable or >96 hours have passed, a 7-day course of oral acyclovir beginning 7-10 days after exposure is recommended 1, 2

Vaccination

The recombinant zoster vaccine (Shingrix) is strongly 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 1
• The vaccine can be considered after recovery from acute shingles to prevent future episodes 1
• Shingrix provides >90% efficacy in preventing future recurrences 1

Common Pitfalls to Avoid

• Do not discontinue antiviral therapy at exactly 7 days if lesions are still forming or have not completely scabbed 1
• Do not rely on clinical diagnosis alone in immunocompromised patients or atypical presentations—laboratory confirmation is needed 1
• Do not use topical antivirals as they are substantially less effective than systemic therapy 1
• Do not delay treatment waiting for the 72-hour window to pass—earlier is always better 1
• Remember that antiviral medications do not eradicate latent virus but help control symptoms and reduce complications 1