Denavir antiviral prescription medication attacks the herpes virus in cold sores and prevents it from further replicating in the system.



Cold sores can cause people pain and embarrassment. Fortunately, there is Denavir, which can help shorten the duration and severity of cold sore breakouts.

Denavir (penciclovir topical) is an antiviral topical cream that is used to treat reoccurring cold sores on the mouth. When used as directed, it can lessen the duration and the symptoms of cold sores and suppress them from reoccurring.

How Does Denavir Work?

Denavir is an antiviral topical cream that attacks the herpes virus in cold sores and prevents it from further replicating in the system. The end result is a lessening of the duration of cold sores and the suppressing of their reoccurrence.

How to take Denavir?

Only use this topical cream exactly as directed to by your doctor or pharmacist. Avoid applying it near the eyes, in the nose, ears or inside of the mouth. Typically this medication will be applied topically 2 times per day to the affected area, for four days with a gap of three days in the treatment week. If you miss an application, simply apply the cream at the first chance you get and continue to use it at the next scheduled application time.

Living with Cold Sores:

Nobody wants to walk around with a noticeably red and irritated cold sore on their face. Often people who suffer from cold sores report that they are reoccurring, this means that several times per year they go through the entire process of treatment once again. With Denavir you can eliminate cold sores fast, and even prevent them from coming back.

How can you Prevent Cold Sores?

The herpes virus is a tricky one, and while it may be nearly impossible to actually prevent it from surfacing on the skin in the form of cold sores, there are effective methods of treatment and suppressive therapy—achieved simply by applying a topical cream to the affected area twice per day.

Denavir Side Effects:

There are some minor side effects which can occur when using this prescription topical cream, they include:

  • Headache
  • Numbness where the cream is applied
  • Tingling where the cream is applied
  • Subtle changes in taste
  • Minor rash at the application site
  • Minor irritation at the application site
  • In very rare cases, an allergic reaction could occur, if you experience any sort of allergic reaction from taking this drug—STOP using it and contact your doctor immediately

Denavir Precautions:

While it is not likely that Denavir will harm a baby if used by a pregnant mother, any women who are pregnant, expecting or nursing should first consult with their doctor before using this drug to avoid any potential complications from occurring. Refrain from using any other topical drugs, creams or lotions during treatment. Ask your doctor if this drug is the right drug for you.

Important Patient Information


IMPORTANT: HOW TO USE THIS INFORMATION: This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.

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). Penciclovir 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 future occurrences.

HOW TO USE: Use this medication at the first sign of infection (such as tingling, burning, redness, or sores). Wash your hands with soap and water before and after applying this medication. Clean and dry the affected areas before applying the medication. Apply a thin layer of penciclovir cream to completely cover the area of the cold sore or the area of tingling/itching/redness/swelling, and rub in gently. Apply the cream as directed by your doctor, usually every 2 hours (except during sleep) for 4 days. Apply to skin only. Do not apply this medication in or near the eyes since this medication can irritate the eyes. If you do get medication in your eyes, flush with plenty of water. Do not apply inside the mouth or nose. Dosage is based on your medical condition 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. Cold sores (herpes) can spread easily. Penciclovir 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.

SIDE EFFECTS: Redness, burning, stinging, or numbness may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly. Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects. A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing. This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist. In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

PRECAUTIONS: Before using penciclovir, tell your doctor or pharmacist if you are allergic to it; or to famciclovir; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details. Before using this medication, tell your doctor or pharmacist your medical history. Tell your doctor if you are pregnant before using this medication. This medication does not pass into breast milk. Consult your doctor before breast-feeding.

DRUG INTERACTIONS: Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

OVERDOSE: This medicine may be harmful if swallowed. If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.

MISSED DOSE: If you miss a dose, use it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Use your next dose at the regular time. Do not double the dose to catch up.

STORAGE: Store this medication at room temperature. Firmly screw the cap back on the tube of medication after each use. Keep all medications away from children and pets. Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.

Prescribing Information

This product information is intended for United States residents only. Before prescribing, please refer to the patient information. You can view the document and also download it on your computer. You may also consider printing out a copy for yourself.

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