No

Antiviral Agent

Topical treatment of herpes simplex labialis (cold sores); potentially used for Epstein-Barr virus infections

B

Previous and significant adverse reactions to famciclovir; hypersensitivity to the product or any of its components

Penciclovir should only be used on herpes labialis on the lips and face; because no data are available, application to mucous membranes is not recommended. Avoid application in or near eyes since it may cause irritation. The effect of penciclovir has not been established in immunocompromised patients.

>10%: Dermatologic: Mild erythema (50%)

1% to 10%: Central nervous system: Headache (5.3%)

<1%: Local anesthesia (0.9%)

Penciclovir is poorly absorbed if ingested orally. Adverse reactions related to oral ingestion are unlikely.

No data reported

In cells infected with HSV-1 or HSV-2, viral thymidine kinase phosphorylates penciclovir to a monophosphate form which, in turn, is converted to penciclovir triphosphate by cellular kinases. Penciclovir triphosphate inhibits HSV polymerase competitively with deoxyguanosine triphosphate. Consequently, herpes viral DNA synthesis and, therefore, replication are selectively inhibited

Measurable penciclovir concentrations were not detected in plasma or urine of healthly male volunteers following single or repeat application of the 1% cream at a dose of 180 mg penciclovir daily (approximately 67 times the usual clinical dose)

Apply cream at the first sign or symptom of cold sore (eg, tingling, swelling); apply every 2 hours during waking hours for 4 days

Reduction in virus shedding, negative cultures for herpes virus; resolution of pain and healing of cold sore lesion

None reported

None reported

No information available to require special precautions

No effects or complications reported

This is not a cure for herpes (recurrences tend to appear within 3 months of original infection), nor will this medication reduce the risk of transmission to others when lesions are present. For external use only. Wash hands before and after application. Apply this film over affected areas at first sign of cold sore. Avoid use of other topical creams, lotions, or ointments unless approved by prescriber. You may experience headache, mild rash, or taste disturbances. Breast-feeding precautions: Consult prescriber if breast-feeding.

Cream: 1% [10 mg/g] (2 g)

Alrabiah FA and Sacks SL, "New Antiherpesvirus Agents. Their Targets and Therapeutic Potential," Drugs, 1996, 52(1):17-32.