What is the recommended treatment for a patient with shingles, especially for those over 60 or with a weakened immune system?

Treatment for Shingles

For immunocompetent adults with shingles, initiate oral valacyclovir 1 gram three times daily for 7 days within 72 hours of rash onset, continuing treatment until all lesions have completely scabbed; for patients over 60 or immunocompromised, use intravenous acyclovir 10 mg/kg every 8 hours for disseminated or severe disease. 1, 2

Antiviral Therapy: The Cornerstone of Treatment

Immunocompetent Patients

First-line oral antiviral options include:

• Valacyclovir 1 gram three times daily for 7 days is the preferred first-line treatment due to superior bioavailability and convenient dosing 2
• Famciclovir 500 mg three times daily for 7 days offers equivalent efficacy with better pharmacokinetics than acyclovir 1, 3
• Acyclovir 800 mg five times daily for 7-10 days remains effective but requires more frequent dosing, potentially reducing adherence 1, 2

Critical timing considerations:

• Treatment must be initiated within 72 hours of rash onset for optimal efficacy in reducing acute pain, accelerating lesion healing, and preventing postherpetic neuralgia 1, 4
• The 48-hour window provides maximum benefit, though the 72-hour cutoff is the standard recommendation 1, 2
• Continue treatment until all lesions have completely scabbed, not just for an arbitrary 7-day period 1

The evidence strongly favors valacyclovir and famciclovir over acyclovir. Meta-analysis demonstrates valacyclovir reduces herpes-zoster-associated pain by 36% at 21-30 days (NNT=3), while famciclovir shows 46% risk reduction at 28-30 days (NNT=3) compared to acyclovir 3. Both agents offer three-times-daily dosing versus acyclovir's five-times-daily regimen 5, 4.

Immunocompromised Patients and Those Over 60

For uncomplicated herpes zoster in immunocompromised patients:

• Oral acyclovir or valacyclovir at standard doses can be used for localized disease 1
• Monitor closely for signs of dissemination or visceral involvement 6

For disseminated or invasive herpes zoster:

• Intravenous acyclovir 10 mg/kg every 8 hours is mandatory for severely immunocompromised hosts, continuing for minimum 7-10 days until all lesions have scabbed 1
• Consider temporary reduction in immunosuppressive medications if clinically feasible 1
• High-dose IV acyclovir remains the treatment of choice for VZV infections in severely compromised hosts 1

Immunocompromised patients face substantially higher risk of dissemination, prolonged viral shedding, and complications. They may develop new lesions for 7-14 days (versus 4-6 days in immunocompetent patients) and heal more slowly 1. Without adequate antiviral therapy, some develop chronic ulcerations with persistent viral replication 1.

Special Populations and Situations

Facial and Ophthalmic Involvement

Facial zoster requires particular urgency due to risk of cranial nerve complications:

• Initiate oral valacyclovir 1 gram three times daily or famciclovir 500 mg three times daily immediately 1
• Escalate to intravenous acyclovir for suspected CNS involvement, severe ophthalmic disease, or complicated facial zoster 1
• Elevation of the affected area promotes drainage of edema 1
• Keep skin well hydrated with emollients to avoid dryness and cracking 1

Renal Impairment

Dose adjustments are mandatory to prevent acute renal failure 1, 2:

• For creatinine clearance 30-49 mL/min: valacyclovir 1 gram every 12 hours 2
• For creatinine clearance 10-29 mL/min: valacyclovir 1 gram every 24 hours 2
• For creatinine clearance <10 mL/min: valacyclovir 500 mg every 24 hours 2
• Monitor renal function at initiation and once or twice weekly during IV acyclovir treatment 1

Acyclovir-Resistant Cases

For proven or suspected acyclovir resistance:

• Foscarnet 40 mg/kg IV every 8 hours until clinical resolution is the treatment of choice 1
• All acyclovir-resistant strains are also resistant to valacyclovir, and most to famciclovir 1
• Resistance is extremely rare in immunocompetent patients but occurs more frequently in immunocompromised patients receiving prolonged suppressive therapy 1

Post-Exposure Prophylaxis

For varicella-susceptible patients exposed to active varicella zoster:

• Varicella zoster immunoglobulin (VZIG) or intravenous immunoglobulin within 96 hours of exposure is recommended 1
• If immunoglobulin unavailable or >96 hours have passed, give 7-day course of oral acyclovir beginning 7-10 days after exposure 1
• High-risk populations include pregnant women, immunocompromised patients, and premature newborns <28 weeks gestation 1

Infection Control

Patients with active shingles must avoid contact with susceptible individuals until all lesions have crusted 1:

• Cover lesions with clothing or dressings to minimize transmission risk 1
• Healthcare workers with herpes zoster should be excluded from duty until all lesions dry and crust 1
• For disseminated zoster (>3 dermatomes), implement both airborne and contact precautions 1
• Physical separation of at least 6 feet from other patients in healthcare settings 1

Prevention of Future Episodes

The recombinant zoster vaccine (Shingrix) is strongly recommended:

• For all adults aged ≥50 years, regardless of prior herpes zoster episodes 1, 7
• Provides >90% efficacy in preventing future recurrences 1
• Should be administered after recovery from current episode 1
• Ideally given before initiating immunosuppressive therapies 1

For patients with frequent recurrences:

• Daily suppressive therapy with acyclovir 400 mg orally twice daily 7
• Alternative: valacyclovir 500 mg once daily or famciclovir 250 mg twice daily 7
• Consider discontinuation after 1 year to reassess recurrence rate 7

Critical Pitfalls to Avoid

• Never use topical antivirals - they are substantially less effective than systemic therapy and are not recommended 1
• Do not discontinue treatment at exactly 7 days if lesions are still forming or have not completely scabbed 1
• Avoid corticosteroids in immunocompromised patients due to increased risk of disseminated infection 1
• Do not delay treatment waiting for laboratory confirmation in typical presentations - clinical diagnosis suffices for immunocompetent patients 1
• Monitor for dissemination in immunocompromised patients - if signs occur, immediately escalate to IV therapy 6