Zovirax Dosage Guide: How Much to Take and When (With Chart)
Understanding Zovirax Uses and DosagesZovirax, known generically as acyclovir, is a widely prescribed antiviral medication that helps control infections caused by herpes [...]
Read MoreZovirax Dosage Guide: How Much to Take and When (With Chart)
Medically reviewed by Alan Lucks | MD, Alan Lucks MDPC Private Practice - New York on January 4th, 2026.
Key Takeaways
- Zovirax (acyclovir) is an antiviral medication used to treat herpes infections, including genital herpes, cold sores, and shingles.
- Dosage varies depending on the condition being treated, patient age, and severity of the infection.
- Typical adult doses range from 200 mg to 800 mg, taken multiple times daily, depending on the form and purpose.
- Children’s dosages are adjusted by weight and age, requiring careful calculation and medical supervision.
- Missed doses should be taken as soon as remembered, but never doubled to catch up.
- Adjustments may be necessary for patients with kidney impairment or other medical conditions.
- For personalized advice and telehealth consultations, Doctronic.ai offers fast, expert care 24/7 at affordable prices.
Understanding Zovirax Uses and Dosages
Zovirax, known generically as acyclovir, is a widely prescribed antiviral medication that helps control infections caused by herpes viruses. Whether you’re dealing with cold sores, shingles, or genital herpes, understanding the correct dosage is crucial for effective treatment and minimizing side effects. This guide breaks down the recommended dosages by condition, age group, and medication form, helping you navigate your treatment with confidence.
Zovirax Dosage Chart
Form |
Strength |
Typical Adult Dose |
Typical Children’s Dose |
Frequency |
Route |
Maximum Daily Dose |
|---|---|---|---|---|---|---|
Tablet |
200 mg |
200 mg to 800 mg |
10 mg/kg |
3 to 5 times daily |
Oral |
3200 mg |
Capsule |
400 mg |
400 mg to 800 mg |
Not typically used |
3 to 5 times daily |
Oral |
3200 mg |
Ointment |
5% |
Apply 5 times daily |
Apply 5 times daily |
Apply 5 times daily |
Topical |
Not applicable |
Injection |
50 mg/mL |
5 to 10 mg/kg |
5 to 10 mg/kg |
Every 8 hours |
Intravenous |
30 mg/kg/day |
Zovirax Dosage by Condition
Genital Herpes
For initial episodes of genital herpes in adults, the typical dosage is 200 mg orally five times a day for 10 days. For recurrent episodes, the dose is often reduced to 200 mg three to five times daily for 5 days. Suppressive therapy, used to reduce outbreak frequency, usually involves 400 mg twice daily.
Cold Sores (Herpes Labialis)
Adults typically take 200 mg orally 5 times daily for 5 days. A topical ointment can be applied 5 times daily for up to 4 days, but oral medication is generally more effective at controlling outbreaks.
Shingles (Herpes Zoster)
The recommended adult dosage is 800 mg orally five times daily for 7 to 10 days. Early treatment is essential to reduce pain and speed healing.
Chickenpox (Varicella)
For children and adults, the dosage depends on weight and severity. Children aged 2 to 12 years typically receive 20 mg/kg orally four times daily for 5 days. Adults may take 800 mg orally four times daily for 5 days.
What is the Typical Zovirax Dose for Adults?
Adult dosages vary widely based on the infection type and severity of the infection. For most oral treatments, doses range from 200 mg to 800 mg, taken three to five times daily. The duration typically spans from 5 to 10 days. Intravenous doses are reserved for severe infections and immunocompromised patients and are administered under strict medical supervision.
What is the Typical Zovirax Dose for Children?
Children’s dosages are weight-based and must be carefully calculated. For oral administration, the typical dose is 10 to 20 mg per kilogram of body weight, given three to five times daily. The exact dose and duration depend on the condition being treated and the child's age. Always follow the pediatrician's guidance closely.
What to Do If You Miss a Dose of Zovirax?
If a dose is missed, take it as soon as you remember. If it is almost time for your next dose, skip the missed one and continue your regular schedule. Do not double the dose to catch up, as this can increase the risk of side effects. Consistency is key to antiviral effectiveness.
How to Adjust Your Zovirax Dose for Certain Medical Conditions
Kidney Impairment Adjustment
Zovirax is primarily eliminated through the kidneys. Patients with renal impairment may require dose adjustments to avoid accumulation and toxicity. Your healthcare provider will determine the appropriate dose based on kidney function tests.
Immunocompromised Patients
Patients with weakened immune systems, such as those undergoing chemotherapy or with HIV/AIDS, may need higher or more frequent doses. These adjustments should only be made by a healthcare professional.
Zovirax Overdose and Warnings
Overdose symptoms may include nausea, vomiting, dizziness, and confusion. In severe cases, seizures or kidney damage can occur. If an overdose is suspected, seek emergency medical attention immediately.
Zovirax should be used cautiously in patients with kidney disease, dehydration, or neurological disorders. Always inform your doctor about your complete medical history and any other medications you are taking to avoid harmful interactions.
Tips for Taking Zovirax Safely
Take Zovirax exactly as prescribed by your healthcare provider.
Stay well hydrated during treatment to help prevent kidney problems.
Do not stop treatment early, even if symptoms improve, unless advised by your doctor.
Avoid sharing your medication with others.
Store the medication at room temperature away from moisture and heat.
Learn More About Zovirax Dosage With Doctronic
Determining the correct Zovirax dosage can be complex, especially when factoring in age, kidney function, and the specific infection. Doctronic.ai offers personalized, AI-powered medical advice that synthesizes the latest peer-reviewed research to answer your questions quickly and accurately. If you need tailored dosage guidance or have concerns about side effects, Doctronic’s telehealth services connect you with licensed doctors 24/7 across all 50 states, often for less than $40 per visit.
Visit Doctronic.ai to get a free AI doctor visit or schedule a video consultation with a real doctor who can review your medical history and help adjust your Zovirax dosage safely.
Frequently Asked Questions
Zovirax can interact with some medications, especially those affecting kidney function. Always inform your doctor about all medications and supplements you are taking to avoid interactions.
Topical Zovirax is generally considered safe during pregnancy, but oral or intravenous forms should only be used if clearly needed and prescribed by a healthcare provider.
Starting treatment as early as possible, ideally within 48 hours of symptom onset, improves effectiveness and reduces the severity and duration of outbreaks.
Zovirax does not cure herpes but helps control symptoms, reduce outbreak frequency, and lower the risk of transmission.
Common side effects include headache, nausea, diarrhea, vomiting, and dizziness. If you experience severe side effects, such as a rash, confusion, or kidney issues, contact your healthcare provider immediately.
Zovirax is a prescription medication. For safe and appropriate use, consult a healthcare professional. Telehealth services like Doctronic.ai can help you get a prescription quickly and safely.
References
The Bottom Line
Effective antiviral treatment relies on the correct dosage and timing. Zovirax is a powerful tool against herpes viruses, but like any medication, it requires careful use. Whether you’re managing a first outbreak or seeking suppressive therapy, staying informed and working with healthcare professionals ensures the best outcomes.
Remember, online resources can provide general guidance, but personalized care is invaluable. Doctronic.ai bridges the gap between cutting-edge AI and human medical expertise, offering you fast, reliable answers and access to doctors whenever you need them.