What is the recommended approach to assess and treat shingles?

Assessment and Treatment of Shingles

The recommended approach for shingles is prompt initiation of oral antiviral therapy (acyclovir, valacyclovir, or famciclovir) within 72 hours of rash onset, with valacyclovir 1 gram three times daily for 7 days being the preferred first-line treatment due to its convenient dosing and high bioavailability. 1, 2, 3

Diagnosis and Assessment

• Diagnosis of shingles is typically made through clinical presentation, characterized by a unilateral dermatomal vesicular rash often preceded by pain or discomfort in the affected dermatome 4, 5
• Laboratory testing can confirm the diagnosis when clinical presentation is atypical:
  • Nucleic acid amplification tests from blister material are highly specific and sensitive (approaching 100%) 6
  • Older technologies like Tzanck smear or rapid antigen detection are less reliable and dependent on sample quality 6
• Serology is not useful for diagnosis of shingles 6

First-Line Treatment Options

• Antiviral therapy should be initiated within 72 hours of rash onset for maximum effectiveness 5, 7
• Recommended antiviral regimens include:
  • Valacyclovir: 1 gram orally 3 times daily for 7 days (preferred due to better bioavailability) 3
  • Acyclovir: 800 mg orally 5 times daily for 7-10 days 8
  • Famciclovir: 500 mg orally 3 times daily for 7 days 9
• Newer agents like valacyclovir or famciclovir with higher oral bioavailability are preferable to acyclovir when oral therapy is appropriate 6

Pain Management

• Pain in shingles may have burning, lancinating, or allodynic qualities and can persist for 2-8 weeks 7
• For acute pain management:
  • Begin with non-opioid analgesics for mild pain 5
  • For moderate to severe pain, consider short-term opioid analgesics 5
• For postherpetic neuralgia (pain persisting after rash resolution):
  • Tricyclic antidepressants (e.g., amitriptyline) or anticonvulsants in low doses 5
  • Topical treatments like capsaicin or lidocaine patches may help in selected patients 5

Special Populations

Immunocompromised Patients

• Immunocompromised patients require more aggressive management due to higher risk of complications 1, 2
• Consider intravenous acyclovir 5 mg/kg every 8 hours for severe cases 1
• Immunomodulators should not be initiated during active shingles 6
• Temporary reduction in immunosuppressive medication should be considered in patients with disseminated or invasive herpes zoster 2

Pregnant Women

• Varicella zoster immune globulin (VZIG) is recommended for VZV-susceptible pregnant women within 96 hours after exposure to VZV 6
• Acyclovir can be used in pregnancy if oral therapy is indicated 6

Prevention

• Vaccination is recommended for prevention of herpes zoster in adults aged 50 years and older 10, 11
• Varicella zoster immune globulin (VZIG) should be administered within 10 days when an unimmunized, seronegative, high-risk patient has had significant exposure to chickenpox or shingles 6

Common Pitfalls to Avoid

• Delaying treatment beyond 72 hours after rash onset significantly reduces antiviral effectiveness 5, 7
• Using topical acyclovir is substantially less effective than oral therapy and is not recommended 1
• Inadequate dosing or duration of therapy may lead to treatment failure and increased risk of complications 1
• Failing to recognize and appropriately manage herpes zoster in immunocompromised patients, who may require more aggressive therapy 1, 2

Follow-up Recommendations

• Monitor for complete resolution of lesions; treatment may need to be extended if healing is incomplete after the initial course 1
• Patients should be advised that lesions are contagious to individuals who have not had chickenpox and should avoid contact with susceptible individuals until lesions have crusted 12
• Assess for development of postherpetic neuralgia, which may require additional treatment approaches 5