Generic Name: penciclovir (pen-SYE-kloe-vir)
Medically reviewed by Drugs.com. Last updated on March 5, 2020.
Commonly used brand name(s)
In the U.S.
Available Dosage Forms:
Therapeutic Class: Antiviral
Pharmacologic Class: Viral DNA Polymerase Inhibitor
Chemical Class: Guanosine Nucleoside Analog
Uses for penciclovir
Penciclovir belongs to the family of medicines called antivirals. Antivirals are used to treat infections caused by viruses. Usually they work for only one kind or group of virus infections.
Topical penciclovir is used to treat the symptoms of herpes simplex virus infections around the mouth (cold sores). Although topical penciclovir will not cure herpes simplex, it may help relieve the pain and discomfort and may help the sores heal faster.
Penciclovir is available only with your doctor's prescription.
Before using penciclovir
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For penciclovir, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to penciclovir or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
There is no specific information comparing the use of topical penciclovir in children with use in other age groups.
Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults. There is no specific information comparing use of penciclovir in the elderly with use in other age groups. However, penciclovir has been used in some older patients and has not been found to cause different side effects or other problems than it does in younger adults.
Studies in women suggest that this medication poses minimal risk to the infant when used during breastfeeding.
Interactions with medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Tell your healthcare professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.
Interactions with food/tobacco/alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.
Other medical problems
The presence of other medical problems may affect the use of penciclovir. Make sure you tell your doctor if you have any other medical problems, especially:
- Immune system problems—It is not known if penciclovir will work properly in patients with these problems
Proper use of penciclovir
Penciclovir should only be used on the lips or face.
Penciclovir is best used as soon as possible after the symptoms of herpes infection (for example, pain, burning, or blisters) begin to appear.
Do not use penciclovir in or near the eyes.
Do not use penciclovir inside the mouth or nose or on other internal parts of the body.
The dose of penciclovir will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of penciclovir. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For topical dosage form (cream):
- For herpes simplex infection (cold sores):
- Adults—Apply to the affected area(s) of the skin every two hours, while awake, for four days.
- Children—Use and dose must be determined by your doctor.
- For herpes simplex infection (cold sores):
If you miss a dose of penciclovir, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Penciclovir side effects
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor as soon as possible if any of the following side effects occur:
- Mild pain, burning, or stinging
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
- Change in sense of taste
- decreased sensitivity of skin, particularly to touch
- redness of the skin
- skin rash
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
More about penciclovir topical
- Side Effects
- During Pregnancy or Breastfeeding
- Dosage Information
- Drug Interactions
- En Español
- 63 Reviews
- Drug class: topical antivirals
- Other brands
Related treatment guides
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.