Penciclovir

These indications are based on manufacturer information for both originator and generic products. For product specific registered indications, please refer to product specific manufacturer information

Registered South African indications:

• Cold sores (herpes labialis)

Contraindications

• Hypersensitivity to the active ingredient or any of its excipients
• Hypersensitivity to famciclovir

Cautions

• Hypersensitivity to cetostearyl alcohol or propylene glycol
• Pregnancy
• Breastfeeding
• Application to mucous membranes
• Application in or near the eyes
• Severe infections
• Immunocompromised patients

Forms avail. in SA and covered in this monograph: cre

Infections caused by:  Herpes simplex virus

Specific doses based on individual indications

Please note that the dosages below should be used in combination with regional guidelines, taking into account local antibiotic sensitivities

Herpes simplex virus infections of the lips and face

• Topical (cre): Apply small quantity to affected area(s), 2hrly during waking hours; Treatment duration: 4 days

Treatment should be started as early as possible after the first sign of an infection

If the condition gets worse or does not improve after 4 days treatment, seek medical advice

Not established for children below 12 years 

Pregnancy

• Caution; not recommended
• There is unlikely to be any cause for concern regarding adverse effects when the cream is used in pregnant women as systemic absorption of penciclovir following topical administration has been shown to be minimal
• Since safety of penciclovir in human pregnancy has not been established, it should only be used during pregnancy on the advice of a doctor, if the potential benefits are considered to outweigh the potential risks associated with treatment
• One study reported the use of penciclovir in human pregnancy and found no statistically significant association with major birth defects. Penciclovir is the active metabolite of the prodrug (famciclovir). Animal reproductive data suggest a low risk. In addition, the drug has not been detected in the plasma or urine after single or repeated topical doses in healthy males. Thus, the risk to an embryo or fetus from maternal use of the agent appears to be nil

Breastfeeding

• Caution
• There is unlikely to be any cause for concern regarding adverse effects when the cream is used in lactating women as systemic absorption of penciclovir following topical administration has been shown to be minimal
• There is no information on excretion of penciclovir in human milk
• Studies in rats show that penciclovir is excreted in the breast milk of lactating female rats given oral famciclovir
• Penciclovir should therefore only be used by breastfeeding mothers on the advice of a doctor, if the potential benefits are considered to outweigh the potential risks associated with treatment

Fertility

• Animal studies have not shown any embryotoxic or teratogenic effects with penciclovir given intravenously (at doses greater than 1200 times those recommended for clinical use via topical application)
• Additionally, animal studies did not show any effects on male and female fertility and general reproductive performance (at doses greater than 1600 times those recommended for clinical use via topical application)
• The results of a wide range of mutagenicity studies in vitro and in vivo indicates that penciclovir does not pose a genotoxic risk to man

Renal Impairment

• No dose adjustment recommended

Hepatic Impairment

• No dose adjustment recommended

Elderly

• No dose adjustment recommended

Porphyria Information

• Not porphyrinogenic (NP)

Drugs in Sport

• Permitted - No warnings

Skin and Subcutaneous Tissue Disorders

• Allergic dermatitis
  - Rash
  - Pruritis
  - Blisters
  - Oedema
• Urticaria
• Application site reactions  
  - Burning
  - Pain
  - Hypoaesthesia

Immune, Blood and Lymphatic System Disorders

• Hypersensitivity

No information available

None routine

Immunocompromised patients

• Penciclovir is not recommended for use in immunocompromised patients. Such patients should consult a physician concerning the treatment of any infection

Penciclovir has demonstrated in vivo and in vitro activity against herpes simplex viruses (types 1 and 2) and varicella zoster virus. In virus-infected cells, penciclovir is rapidly and efficiently converted into a triphosphate (mediated via virusinduced thymidine kinase). Penciclovir triphosphate persists in infected cells for more than 12 hours where it inhibits replication of viral DNA and has a half-life of 9, 10 and 20 hours in cells infected with varicella zoster virus, herpes simplex virus type 1 and herpes simplex virus type 2 respectively.

Spectrum of activity: Herpes simplex virus

Cream (per g) 0.01g

• Fenivir Cold Sore Cream (Austell Laboratories) originator