Herpesvirus 1, Human
Human Herpesvirus 1 (HSV-1) is a common viral pathogen that primarily causes oral herpes infections, presenting as cold sores or fever blisters around the mouth. It can also cause herpes simplex encephalitis, particularly in immunocompromised individuals, and is occasionally associated with genital infections.
HSV-1 is a widespread virus that causes oral herpes and can lead to more serious infections of the brain in vulnerable populations.
Key facts at a glance
- RxNorm
- 1316105
- Generic
- Herpesvirus 1, Human
- Class
- unclassified
- Brands
- Imlygic
- Availability
- rx
- Lactation
- unknown
- Routes
- —
- Forms
- injection
- 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.
HSV-1 infection presents as vesicles and ulcers on the lips, mouth, and face (orolabial herpes), and may cause keratitis of the eye, herpes gladiatorum (skin infections in athletes), and potentially life-threatening encephalitis in rare cases.
HSV-1 is a double-stranded DNA virus that enters epithelial cells, replicates, and then establishes latency in sensory nerve ganglia. During reactivation, the virus travels along sensory nerves back to skin or mucous membranes, causing recurrent lesions.
HSV-1 is highly contagious through direct contact with infected lesions or saliva. The virus cannot be eliminated from the body once acquired and may reactivate periodically, especially during periods of stress, illness, or immunosuppression. Antiviral medications such as acyclovir, valacyclovir, or famciclovir are used to treat active infections and reduce symptom duration.
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 31, 2026. · Read our editorial policy