WHY is this medicine prescribed?
Penciclovir is used on the lips and faces of adults to treat cold sores caused by herpes simplex virus. Penciclovir does not cure herpes infections but decreases pain and itching if applied when the earliest symptoms first appear.
This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.
HOW should this medicine be used?
Penciclovir comes as a cream. It is usually used externally every 2 hours while you are awake for 4 days. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist or doctor to explain any part you do not understand. Use penciclovir exactly as directed. Do not use more or less of it or use it more often than prescribed by your doctor. Use this medication as soon as possible after symptoms appear.
Clean and dry the area before applying the cream to avoid spreading the infection. Rub the cream in gently, using enough cream to cover all sores completely.
Continue to use penciclovir even if you feel well. Do not stop using penciclovir without talking to your doctor.
What SPECIAL PRECAUTIONS should I follow?
Before using penciclovir,
What should I do IF I FORGET to take a dose?
Apply the missed dose as soon as you remember it and apply any remaining doses for that day at evenly spaced intervals. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not apply a double dose to make up for a missed one.
What SIDE EFFECTS can this medicine cause?
Penciclovir may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
What should I know about STORAGE and DISPOSAL of this medication?
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).
Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location - one that is up and away and out of their sight and reach. http://www.upandaway.org
Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website http://goo.gl/c4Rm4p for more information.
What OTHER INFORMATION should I know?
Keep all appointments with your doctor. Penciclovir should only be used on the lips and face. Avoid getting it in your eyes. Keep the infected area clean and dry.
Do not let anyone else use your medication. Ask your pharmacist any questions you have about refilling your prescription. If you still have symptoms of infection after you finish the penciclovir, call your doctor.
Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines, vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies.
This report on medications is for your information only, and is not considered individual patient advice. Because of the changing nature of drug information, please consult your physician or pharmacist about specific clinical use.
The American Society of Health-System Pharmacists, Inc. represents that the information provided hereunder was formulated with a reasonable standard of care, and in conformity with professional standards in the field. The American Society of Health-System Pharmacists, Inc. makes no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, with respect to such information and specifically disclaims all such warranties. Users are advised that decisions regarding drug therapy are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and the information is provided for informational purposes only. The entire monograph for a drug should be reviewed for a thorough understanding of the drug's actions, uses and side effects. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information is not a substitute for medical care.
AHFS® Patient Medication Information™ Copyright, 2025. The American Society of Health-System Pharmacists®, 4500 East-West Highway, Suite 900, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.
Selected Revisions: December 15, 2017.