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Drug

Acyclovir

Pronounced

"ay-SYE-kloe-vir"

Uses

This medication is used to treat "cold sores/fever blisters" (herpes labialis). It can speed up healing of the sores and decrease symptoms (such as tingling, pain, burning, itching). Acyclovir belongs to a class of medications known as antivirals. It works by stopping the growth of the virus. This medication does not cure herpes, and it does not prevent passing the infection to someone else. It does not prevent a future occurrence.

How to Use This Medication

Read the Patient Information Leaflet if available from your pharmacist before you start using acyclovir and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

Use this medication at the first sign of infection (such as tingling, burning, redness). Wash your hands with soap and water before and after applying this medication. Clean and dry the affected areas before applying the medication. Apply to the affected area and rub in gently as directed by your doctor, usually 5 times a day (every 3 to 4 hours) for 4 days for cold sores. Apply enough cream to cover all affected areas (red/tingling/burning areas, sores).

Apply to skin only. Do not apply this medication in the eyes or nose, inside the mouth, or inside the vagina. If you do get medication in those areas, flush with plenty of water.

The dosage is based on your medical condition, type of infection, and response to treatment. Do not use this drug more often or for longer than prescribed.

Use this medication regularly to get the most benefit from it. This medication works best when the amount of drug absorbed by the skin stays at a constant level. Use this drug at evenly spaced intervals. To help you remember, use it at the same times each day.

To prevent washing off the medication, do not bathe, shower, or swim right after applying it.

Do not apply other skin products (such as drugs, cosmetics, sun screens, or lip balms) unless told to do so by your doctor. Do not cover the area with plastic or waterproof bandages unless told to do so by your doctor.

Cold sores (herpes) can spread easily. Acyclovir cream does not prevent the spread of herpes. Avoid close physical contact with others (such as kissing) during an outbreak until the cold sores have completely healed. Also, try not to touch the cold sore, and wash your hands if you do touch the cold sore.

Tell your doctor if your condition lasts or gets worse after treatment is finished.

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Drug information is selected from data included with permission and copyrighted by First DataBank, Inc. This is a summary and does not contain all possible information about this product. For complete information about this product or your specific health needs, ask your healthcare professional. Always seek the advice of your healthcare professional if you have any questions about this product or your medical condition. This information is not intended as individual medical advice and does not substitute for the knowledge and judgment of your healthcare professional. This information does not contain any assurances that this product is safe, effective or appropriate for you.

This information is intended only for residents of the United States. Products sold under the same brand names in other countries may contain different ingredients.

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Information expires December 2025.