Acyclovir
Zovirax (acyclovir) is an antiviral medication used to treat infections caused by herpes simplex and varicella-zoster viruses, including cold sores, genital herpes, chickenpox, and shingles. It is available in topical, oral, and intravenous formulations and is prescribed for both initial outbreaks and recurrent episodes.
Zovirax is an antiviral used to treat herpes simplex and varicella-zoster virus infections like cold sores and shingles.
Key facts at a glance
- RxNorm
- 152535
- Generic
- Zovirax
- Class
- brand-name
- Brands
- —
- Availability
- rx
- Lactation
- unknown
- Routes
- —
- Forms
- —
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Treatment of herpes simplex virus infections (cold sores, genital herpes), varicella-zoster virus infections (chickenpox, shingles), and herpes encephalitis. Also used for prevention in immunocompromised patients.
Acyclovir is converted to its active form inside infected cells, where it inhibits viral DNA polymerase and terminates viral DNA synthesis, preventing the virus from replicating.
Most effective when started at the first sign of symptoms. Not a cure for herpes infections. May cause headache, nausea, or local skin reactions. Should be used with caution in patients with kidney impairment. Oral and IV forms require adequate hydration.
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 27, 2026. · Read our editorial policy