Zovirax Cold Sore Cream

Zovirax Cold Sore Cream is a smooth white cream containing 100mg aciclovir equivalent to 5%w/w in a water miscible base.

Cream.

Zovirax Cold Sore Cream is indicated for the treatment of Herpes simplex virus infections of the lips and face (Herpes labialis).

Zovirax COLD SORE Cream should be applied five times daily at approximately four hourly intervals omitting the night time application. It is important to start treatment as early as possible after the start of an infection, ideally during the prodromal period.

Treatment should be continued for 5 days. If healing has not occurred, treatment may be continued for up to an additional 5 days. If lesions are still present after 10 days, users should be advised to consult a doctor.

Users should wash their hands before and after applying the cream, and avoid unnecessary rubbing of the lesions or touching them with a towel, to avoid aggravating or transferring the infection.

Zovirax COLD SORE Cream is contraindicated in patients known to be hypersensitive to aciclovir, valaciclovir or propylene glycol.

Zovirax COLD SORE Cream should only be used on cold sores on the mouth and face. It is not recommended for application to mucous membranes, such as in the mouth or eye and must not be used to treat genital herpes. Particular care should be taken to avoid contact with the eye. People with particularly severe Herpes labialis should be encouraged to seek medical advice.

Cold sore sufferers should be advised to avoid transmitting the virus, particularly when active lesions are present.

Zovirax COLD SORE Cream is not recommended for use by people who know that they are immunocompromised. Such individuals should be encouraged to consult a physician concerning the treatment of any infection.

No clinicall significant interactions have been identified.

A post-marketing aciclovir pregnancy registry has documented pregnancy outcomes in women exposed to any formulation of Zovirax. The registry findings have not shown an increase in the number of birth defects amongst Zovirax exposed subjects compared with the general population and any birth defects showed no uniqueness or consistent pattern to suggest a common cause. Systemic exposure to aciclovir from topical application of Zovirax COLD SORE Cream is very low.

Systemic administration of aciclovir in internationally accepted standard tests did not produce embryotoxic or teratogenic effects in rabbits, rats or mice.

In a non-standard test in rats, foetal abnormalities were observed but only following such high subcutaneous doses that maternal toxicity was produced. The clinical relevance of these findings is uncertain.

Limited human data show that aciclovir does pass into breast milk following systemic administration. However, the dosage received by a nursing infant following maternal use of Zovirax COLD SORE Cream would be insignificant.

None known.

Transient burning or stinging may follow application of Zovirax COLD SORE Cream in some users.

Mild drying or flaking of the skin has occurred in about 5% of users.

Erythema and itching have been reported in a small proportion of users.

Contact dermatitis has been reported rarely following application. Where sensitivity tests have been conducted, the reactive substances have most often been shown to be components of the cream base rather than aciclovir.

There have been very rare reports of immediate hypersensitivity reactions including angioedema with topical aciclovir.

No untoward effects would be expected if the entire 2g contents of Zovirax COLD SORE cream containing 100mg of aciclovir were ingested orally.

Aciclovir is an antiviral agent which is highly active in vitro against Herpes simplex virus (HSV) types I and II. Toxicity to mammalian host cells is low.

Aciclovir is phosphorylated after entry into herpes infected cells to the active compound aciclovir triphosphate. The first step in this process is dependent on the presence of the viral-coded thymidine kinase. Aciclovir triphosphate acts as an inhibitor of and substrate for the herpes specified DNA polymerase preventing further viral DNA synthesis without affecting normal cellular processes.

Pharmacology studies have shown only minimal systemic absorption of aciclovir following repeated topical administration of Zovirax COLD SORE Cream.

The results of a wide range of mutagenicity tests in vitro and in vivo indicate that aciclovir does not pose a genetic risk to man.

Aciclovir was not found to be carcinogenic in long-term studies in the rat and the mouse.

Largely reversible adverse effects on spermatogenesis in association with overall toxicity in rats and dogs have been reported only at systemic doses of aciclovir greatly in excess of those employed therapeutically. Two-generation studies in mice did not reveal any effect of orally administered aciclovir on fertility.

There is no information on of the effect of Zovirax Cold Sore Cream on human female fertility. In patients with normal sperm count, chronically administered oral aciclovir has been shown to have no clinically significant effect on sperm count, motility or morphology.

Poloxamer 407
White Soft Paraffin
Cetostearyl Alcohol*
Liquid Paraffin
Dimethicone
Sodium Lauryl Sulphate*
Propylene Glycol
Purified Water

* Alternatively emulsifying wax

Incompatibilities

Not known.

Aluminium Tube 5 years
Pump Dispenser Pack 2 years

Store below 25 °C.
Do not refrigerate.

Aluminium Tube 2g
Pump Dispenser Pack 2g

For external use only.

Pharmacy Only Medicine

Zovirax is a trade mark of the Glaxo Wellcome Group of Companies.