Varicella (Chickenpox)
NICE CKS Chickenpox. Last revised Nov 2023.
Guidelines
Investigation and Diagnosis
Clinical diagnosis is sufficient for most cases based on the characteristic, intensely pruritic, chickenpox rash:
- Small erythematous macules → papules → vesicles, pustules (lesions can be present in varying stages of development, simultaneously)
Laboratory tests can be used to confirm the diagnosis but are not recommended in primary care
- Most sensitive/specific: PCR
- Other: Viral culture / Direct fluorescence antibody testing
Management
For chickenpox in pregnancy, see a separate article.
Referral
- Suspicion of serious complications (inc: pneumonia, encephalitis, severe secondary bacterial skin infections) → Admit
- Seek immediate specialist advise for:
- Immunocompromised patients
- Neonates
Symptomatic Management
Symptomatic treatment is the mainstay of management for uncomplicated varicella
NICE CKS recommends the following:
- Fever causing distress
- Paracetamol (avoid NSAIDs)
- Itch alleviation
- Calamine lotion
- Chlorphenamine (if >1 y/o)
NSAIDs are avoided in patients with varicella (chickenpox) because their use is associated with an increased risk of severe skin and soft tissue bacterial complications, including cellulitis, abscess formation, and necrotizing fasciitis.[Ref]
Antiviral Therapy
NICE CKS says to consider antivirals in the following:
- Immunocompetent >14 y/o that is not pregnant, and
- Presents <24 hours of rash onset, and
- Particularly for severe chickenpox or those at risk of complications (e.g. smokers)
Choice of antiviral therapy: aciclovir 800mg 5 times a day for 7 days
Antiviral therapy is not recommended for otherwise healthy young children (<14 y/o) with uncomplicated chickenpox.