Management of Chickenpox
For immunocompetent adults and adolescents with chickenpox, initiate oral acyclovir 800 mg five times daily within 24 hours of rash onset and continue for 5-7 days, while immunocompromised patients require intravenous acyclovir 10 mg/kg every 8 hours regardless of timing. 1, 2
Initial Assessment and Risk Stratification
The management approach depends critically on three factors: immune status, age, and timing of presentation relative to rash onset. 2
High-Risk Populations Requiring Antiviral Therapy
- Immunocompromised patients (HIV, cancer, chronic immunosuppression, high-dose corticosteroids ≥20 mg/day prednisolone for ≥2 weeks) require immediate IV acyclovir regardless of when they present 3, 4
- Pregnant women exposed to varicella should receive varicella-zoster immune globulin (VZIG) within 96 hours of exposure 4
- Neonates born to mothers with varicella from 5 days before to 2 days after delivery must receive VZIG regardless of maternal VZIG status 4
- Premature infants <28 weeks gestation or <1,000 g require VZIG after exposure regardless of maternal immunity 4
- Adults and adolescents (higher risk of severe disease and complications compared to children) 2, 5
Treatment Protocols by Patient Category
Immunocompetent Adults and Adolescents
Oral antiviral therapy is indicated if presenting within 24 hours of rash onset: 1, 2
- Acyclovir 800 mg orally five times daily for 5-7 days (FDA-approved regimen) 1
- Treatment initiated within 24 hours of rash onset in controlled studies showed efficacy 1
- No data support treatment initiated >72 hours after rash onset 1
- Maintain adequate hydration during treatment 1
Alternative agents with better bioavailability: 6
- Valacyclovir 1000 mg three times daily for 7 days (requires less frequent dosing, improving adherence) 6
Immunocompromised Patients
IV acyclovir is mandatory regardless of presentation timing: 4, 7
- Acyclovir 10 mg/kg IV every 8 hours for minimum 7-10 days and until all lesions have completely crusted 4, 7
- High-dose IV acyclovir remains the treatment of choice for severely compromised hosts 8
- Monitor renal function closely with dose adjustments for renal impairment 8
- Consider temporary reduction of immunosuppressive medications if clinically feasible 8
Pregnant Women
Post-exposure prophylaxis is the priority: 4
- VZIG within 96 hours of exposure is strongly preferred for VZV-susceptible pregnant women 4
- VZIG prevents maternal complications but does not prevent fetal infection or congenital varicella syndrome 4
- If VZIG unavailable or >96 hours post-exposure, acyclovir 20 mg/kg (maximum 800 mg) four times daily for 5-7 days starting 7-10 days after exposure 4
- Acyclovir is FDA Pregnancy Category B with no increased birth defects in 596 first-trimester exposures 4
Healthy Children
Symptomatic therapy is usually adequate: 9, 2
- Chickenpox in otherwise healthy children is typically self-limited with mild to moderate severity 1
- Antiviral therapy may be considered if presenting within 24 hours of rash onset 1
- Treatment was initiated within 24 hours in controlled studies; no data exist for later initiation 1
Symptomatic Management for All Patients
Supportive care measures: 9
- Maintain adequate hydration 1
- Antipyretics for fever (avoid aspirin due to Reye's syndrome risk in children)
- Antihistamines for pruritus
- Topical calamine lotion for symptomatic relief
Antibiotic therapy only for secondary bacterial superinfection: 9
- Co-amoxiclav or ceftriaxone for documented bacterial complications 9
- Not indicated prophylactically in uncomplicated cases
Infection Control Measures
Isolation precautions are critical: 3
- Airborne precautions (negative air-flow rooms) and contact precautions for all hospitalized patients with varicella 3
- Maintain precautions until all lesions are dry and crusted 3
- Patients are infectious up to 2 days before rash onset through lesion crusting 3
- Avoid contact with susceptible individuals, especially high-risk populations 8
Post-Exposure Management of Contacts
For susceptible exposed individuals: 3, 4
- VZIG within 96 hours for high-risk susceptible contacts (immunocompromised, pregnant, neonates, premature infants) 4
- If VZIG unavailable or >96 hours, acyclovir prophylaxis starting 7-10 days post-exposure 3, 4
- Varicella vaccination within 3-5 days of exposure may modify disease if infection has not yet occurred 3
- Monitor exposed susceptible persons daily for fever, skin lesions, and systemic symptoms during days 10-21 after exposure 3
Vaccination Considerations
Post-recovery vaccination: 4
- Varicella vaccine should be considered after recovery for those who remain susceptible 4
- Live varicella vaccine is contraindicated during active infection and in patients receiving immunosuppressive therapy 3
- Immunomodulators should be withheld for 4 weeks after live vaccine administration 3
- Live vaccines should be avoided for at least 3 months after discontinuing immunosuppressive therapies 3
Critical Pitfalls to Avoid
- Do not delay IV acyclovir in immunocompromised patients waiting for the 24-hour window—they require immediate treatment regardless of timing 4, 7
- Do not use topical acyclovir—it is substantially less effective than systemic therapy 8
- Do not administer live varicella vaccine during active infection or to immunocompromised patients 3
- Do not use corticosteroids during active varicella in immunocompromised patients—this increases risk of severe disease and dissemination 8
- Do not initiate oral antivirals >72 hours after rash onset in immunocompetent patients—no data support efficacy 1
- Do not forget renal dose adjustments for acyclovir to prevent nephrotoxicity 1
Monitoring During Treatment
For patients on IV acyclovir: 8
- Monitor renal function at initiation and once or twice weekly during treatment 8
- Assess for thrombotic thrombocytopenic purpura/hemolytic uremic syndrome in immunocompromised patients 8
- Continue treatment until all lesions have completely scabbed, not just for arbitrary duration 8
For acyclovir resistance (rare): 8