What is the recommended treatment for shingles?

Treatment of Shingles (Herpes Zoster)

For immunocompetent adults with uncomplicated shingles, initiate oral valacyclovir 1 gram three times daily or famciclovir 500 mg three times daily for 7-10 days, continuing treatment until all lesions have completely scabbed. 1, 2, 3

First-Line Oral Antiviral Options

The three FDA-approved oral antivirals are equally effective for treating shingles, but differ in dosing convenience 1, 4:

• Valacyclovir 1 gram three times daily for 7 days - preferred due to superior bioavailability and convenient dosing 1, 2, 5
• Famciclovir 500 mg three times daily for 7 days - equivalent efficacy to valacyclovir with three-times-daily dosing 1, 3, 4
• Acyclovir 800 mg five times daily for 7-10 days - effective but requires more frequent dosing, which may reduce adherence 1, 4, 6

Critical Timing and Duration

• Initiate treatment within 72 hours of rash onset for optimal efficacy in reducing acute pain, accelerating lesion healing, and preventing postherpetic neuralgia 1, 6, 7
• Treatment within 48 hours is ideal, but the 72-hour window is the maximum timeframe for optimal benefit 1
• Continue treatment until ALL lesions have completely scabbed, not just for an arbitrary 7-day period - this is the key clinical endpoint 1
• Do not discontinue at exactly 7 days if lesions are still forming or have not completely scabbed 1

Indications for Intravenous Acyclovir

Switch to IV acyclovir 10 mg/kg every 8 hours for 1:

• Disseminated herpes zoster (multi-dermatomal or visceral involvement)
• Severely immunocompromised patients (active chemotherapy, HIV with low CD4 count, organ transplant recipients)
• CNS complications or suspected meningitis/encephalitis
• Complicated ophthalmic disease
• Patients unable to tolerate oral medications

Continue IV therapy for minimum 7-10 days and until clinical resolution is attained 1

Special Populations

Immunocompromised Patients

• Immediately initiate IV acyclovir 10 mg/kg every 8 hours for patients on active chemotherapy, proteasome inhibitors, or with severely compromised immunity 1
• Consider temporary reduction in immunosuppressive medications in consultation with the prescribing specialist 1
• Monitor for disseminated disease and visceral involvement 1, 7
• May require extended treatment duration beyond 7-10 days as lesions develop over longer periods (7-14 days) and heal more slowly 1

Facial/Ophthalmic Involvement

• Requires urgent treatment due to risk of vision-threatening complications and cranial nerve involvement 1
• Initiate oral valacyclovir 1 gram three times daily or famciclovir 500 mg three times daily within 72 hours 1
• Consider ophthalmology referral for any periocular involvement 6
• Escalate to IV acyclovir if severe ophthalmic disease or suspected CNS involvement 1

Renal Impairment

• Mandatory dose adjustments to prevent acute renal failure 1
• For famciclovir in herpes zoster: 500 mg every 8 hours for CrCl ≥60 mL/min, with further reductions for lower clearance 1
• Monitor renal function at initiation and once or twice weekly during IV acyclovir treatment 1

Adjunctive Therapies

Corticosteroids

• Prednisone may be used as adjunctive therapy to antivirals in select cases of severe, widespread shingles 1
• Avoid in immunocompromised patients due to increased risk of disseminated infection 1
• Contraindicated in patients with poorly controlled diabetes, history of steroid-induced psychosis, or severe osteoporosis 1
• Evidence for benefit in preventing postherpetic neuralgia is inconsistent 6, 8

Pain Management

• Acute pain management should be addressed concurrently with antiviral therapy 1, 6
• Topical anesthetics provide minimal benefit and are not recommended as primary therapy 1

What NOT to Do

• Never use topical acyclovir - it is substantially less effective than systemic therapy 1, 9
• Do not use valacyclovir 8 grams per day in immunocompromised patients due to risk of hemolytic uremic syndrome/thrombotic thrombocytopenic purpura 10
• Do not rely on clinical diagnosis alone in immunocompromised patients - obtain laboratory confirmation 1

Monitoring and Resistance

• If lesions fail to begin resolving within 7-10 days, suspect acyclovir resistance 1
• Obtain viral culture with susceptibility testing if resistance suspected 1
• For proven or suspected acyclovir resistance, use foscarnet 40 mg/kg IV every 8 hours 1, 9

Prevention

• Recombinant zoster vaccine (Shingrix) is recommended for all adults aged 50 years and older, regardless of prior herpes zoster episodes 1
• Ideally administer before initiating immunosuppressive therapies 1
• Vaccination after recovery can prevent future episodes 1

Common Pitfalls

• Starting treatment after 72 hours significantly reduces efficacy, though some benefit may still occur 1, 5
• Stopping treatment at exactly 7 days when lesions have not fully scabbed leads to inadequate viral suppression 1
• Failing to escalate to IV therapy in immunocompromised patients with disseminated disease 1
• Using inadequate acyclovir dosing (400 mg TDS is for genital herpes, NOT shingles) 1
• Not adjusting doses for renal impairment, risking acute renal failure 1