From the Guidelines
For varicella (chickenpox) infection, the recommended dose of acyclovir is 20 mg/kg body weight (max 400 mg/dose) orally three times daily for 5-14 days in children under 45 kg, and 400 mg/dose orally twice daily for 5-14 days in adults and adolescents. When considering the treatment of varicella infection, it's crucial to prioritize the patient's age and weight to determine the appropriate acyclovir dosage 1. The dosage guidelines are as follows:
- For children under 45 kg, the dose is 20 mg/kg body weight (max 400 mg/dose) orally three times daily for 5-14 days 1.
- For adults and adolescents, the dose is 400 mg/dose orally twice daily for 5-14 days 1. It's essential to initiate treatment as soon as possible after symptom onset to maximize the effectiveness of acyclovir 1. Key considerations in the treatment of varicella infection include:
- Prompt initiation of treatment, ideally within 24 hours of symptom onset
- Completion of the full treatment course, even if symptoms improve
- Maintenance of adequate hydration during treatment
- Monitoring for common side effects, such as nausea, headache, and diarrhea.
From the FDA Drug Label
Treatment of Chickenpox: Children (2 years of age and older):20 mg/kg per dose orally 4 times daily (80 mg/kg/day) for 5 days. Children over 40 kg should receive the adult dose for chickenpox Adults and Children over 40 kg: 800 mg 4 times daily for 5 days. The dose of acyclovir for varicella (chickenpox) infection is:
- For children (2 years of age and older) weighing less than 40 kg: 20 mg/kg per dose orally 4 times daily (80 mg/kg/day) for 5 days
- For adults and children over 40 kg: 800 mg 4 times daily for 5 days 2
From the Research
Dose of Acyclovir for Varicella Infection
- The dose of acyclovir for varicella infection is 20 mg per kilogram of body weight four times daily for five days, as stated in the study 3.
- Another study 4 mentions that the dose is 80 mg/kg/day up to a maximum of 3,200 mg/day in four divided doses.
- It is also recommended that intravenous doses of 500 mg/m2 or 10 mg/kg every 8 hours or oral doses of 800 mg five times a day are used, as mentioned in the study 5.
Administration and Duration
- Acyclovir treatment should be initiated within the first 24 hours of rash onset, as stated in the studies 4 and 3.
- The duration of treatment is typically 5 days, as mentioned in the studies 4 and 3.
- A 7-day course of acyclovir provided no additional benefit compared to a 5-day course, as stated in the study 4.