Can shingles occur bilaterally, specifically in the axillary (armpit) region, with symptoms of pruritus (itching) and burning irritation, and what is the treatment for this condition?

Shingles (Herpes Zoster) Presentation and Treatment of Itching and Burning Irritation

Shingles typically does not occur bilaterally (on both sides simultaneously) as it normally affects a single dermatome on one side of the body, following the path of a specific nerve root. Bilateral presentation would be highly atypical and should prompt consideration of alternative diagnoses 1.

Typical Presentation of Shingles

Shingles (herpes zoster) is caused by reactivation of the varicella-zoster virus that remains dormant in sensory ganglia after a primary chickenpox infection. The classic presentation includes:

• Prodromal pain preceding rash by 2-3 days
• Unilateral distribution following a dermatome
• Progression from erythematous maculopapular rash to vesicles that eventually crust
• Burning pain, itching, and irritation in the affected area

The rash typically lasts 7-10 days, with complete healing within 2-4 weeks 2.

Atypical Presentations

While bilateral presentation is rare, some atypical presentations of shingles have been documented:

• Painless shingles (particularly in elderly patients) 3
• Presentation mimicking acute abdomen before skin lesions appear 4
• Involvement of unusual locations like vulvar region 5

Itching in Shingles

Pruritus (itching) is a common but often underrecognized symptom of shingles:

• Can occur during acute phase or persist as postherpetic itch (PHI)
• May accompany or occur instead of pain
• Can be mild to severe and potentially disabling
• More common in shingles affecting the head, face, and neck compared to torso 6

Treatment of Shingles-Associated Itching and Burning

Antiviral Therapy

• Start antiviral medication within 72 hours of rash onset for maximum effectiveness 2
• Options include:
  • Acyclovir (800 mg 5 times daily for 7-10 days)
  • Valacyclovir (1000 mg 3 times daily for 7 days)
  • Famciclovir (500 mg 3 times daily for 7 days)

Symptomatic Relief for Itching and Burning

• Topical treatments:

  • Calamine lotion for mild itching
  • Lidocaine patches (5%) for localized areas
  • Cool compresses to reduce inflammation and soothe irritation

• Oral medications:

  • Antihistamines (diphenhydramine, hydroxyzine) for itching
  • Gabapentin or pregabalin for neuropathic symptoms including itching and burning
  • Tricyclic antidepressants (amitriptyline, nortriptyline) at low doses for neuropathic symptoms
  • Short course of oral corticosteroids may be considered in patients without contraindications

Special Considerations

• If lesions occur near the eyes, urgent ophthalmologic consultation is required to prevent vision complications 2
• Patients with severe or persistent symptoms may require stronger pain management, including narcotics
• Capsaicin cream may help with persistent itching but should be used cautiously

Important Caveats

• Bilateral rash in the bend of arms with itching and burning should prompt consideration of alternative diagnoses:

  • Contact dermatitis
  • Drug reaction
  • Atopic dermatitis
  • Sweet's syndrome 1
  • Other viral exanthems

• Laboratory confirmation is important when clinical presentation is atypical:

  • PCR testing of vesicular fluid is the most sensitive and specific test
  • Direct fluorescent antibody testing
  • Viral culture

If symptoms persist beyond 1-3 months after resolution of the rash, this may represent postherpetic neuralgia or postherpetic itch, which require specialized management approaches including tricyclic antidepressants, anticonvulsants, and possibly nerve blocks 2.