What is the recommended treatment for chicken pox in a teenager?

Treatment of Chickenpox in Teenagers

For otherwise healthy teenagers with chickenpox, oral acyclovir 800 mg four times daily for 5 days is the recommended treatment, ideally initiated within 24 hours of rash onset to reduce disease severity and duration. 1

Antiviral Therapy Indication

• Adolescents are at higher risk for severe chickenpox and complications compared to younger children, making antiviral treatment particularly important in this age group 2
• The FDA-approved dosing for teenagers (over 40 kg) is 800 mg orally four times daily for 5 days 1
• Treatment should be initiated at the earliest sign or symptom of chickenpox, ideally within 24 hours of rash onset for maximum efficacy 1
• Therapy initiated more than 24 hours after onset may still provide benefit, though efficacy data beyond 24 hours is limited 1

Clinical Benefits of Acyclovir

• In clinical trials, acyclovir treatment shortened time to 50% healing, reduced maximum number of lesions, decreased median number of vesicles, and reduced fever, anorexia, and lethargy 1
• The medication does not interfere with development of varicella-zoster virus-specific immunity 1

Supportive Care Measures

• Lukewarm baths with colloidal oatmeal can relieve itching 3
• Avoid ibuprofen due to association with severe secondary bacterial infections, particularly Group A streptococcus and necrotizing fasciitis 4
• Acetaminophen may be used for fever management if needed 4

Isolation Requirements

• The teenager must remain isolated until all lesions have crusted over, typically 5-7 days after rash onset, to prevent transmission 3
• Chickenpox is extremely contagious, with more than 90% of unvaccinated exposed individuals becoming infected 5

Special Considerations Requiring Immediate Specialist Referral

• Immunocompromised teenagers require intravenous acyclovir rather than oral therapy 1
• Signs of complications warranting urgent evaluation include: respiratory symptoms suggesting pneumonitis, neurological symptoms indicating CNS involvement, or signs of severe secondary bacterial infection 4, 6
• Varicella disease is more severe in adolescents and adults compared to younger children, with higher rates of complications including pneumonia and disseminated disease 2, 5

Renal Dosing Adjustments

• For teenagers with renal impairment (creatinine clearance 10-25 mL/min/1.73 m²): reduce to 800 mg every 8 hours 1
• For severe renal impairment (creatinine clearance 0-10 mL/min/1.73 m²): reduce to 800 mg every 12 hours 1

Vaccination Status Considerations

• If the teenager has only received one dose of varicella vaccine previously, they should receive a second dose once fully recovered from the acute infection 3
• Susceptible household contacts who have been exposed may benefit from varicella vaccine if administered within 3-5 days of exposure 3