ZOVIRAX

INSTRUCTIONS FOR MEDICAL USE OF THE MEDICINAL PRODUCT ZOVIRAX (ZOVIRAX)

Composition:

Active substance: acyclovir; 1 g of cream contains 50 mg of acyclovir;

Excipients: propylene glycol, white soft paraffin, mineral oil, cetylstearyl alcohol, arlacel 165, poloxamer, sodium lauryl sulfate, dimethicone, purified water.

Pharmaceutical form. Cream.

Main physicochemical characteristics: cream ranging from white to off-white, homogeneous, free from particles, lumps and foreign inclusions, without signs of phase separation.

Pharmacotherapeutic group. Antiviral agents. Acyclovir. ATC code D06B B03.

Pharmacological Properties.

Pharmacodynamics.

Acyclovir is an antiviral agent that has high activity in vitro against herpes simplex virus types I and II. Its toxic effect on host cells is minimal. After entering virus-infected cells, acyclovir is phosphorylated to form the active compound, acyclovir triphosphate. The first step of this process depends on the presence of virus-encoded thymidine kinase. Acyclovir triphosphate acts as both an inhibitor and a substrate for viral DNA polymerase, thereby preventing further viral DNA synthesis without affecting normal cellular processes.

Pharmacokinetics.

Pharmacokinetic studies have shown minimal systemic absorption of acyclovir following repeated topical application of the cream.

Clinical characteristics.

Indications. Treatment of lip and facial infections caused by herpes simplex virus (Herpes labialis).

Contraindications. Hypersensitivity to acyclovir, valacyclovir, propylene glycol, or to any of the other components of the cream.

Interaction with other medicinal products and other forms of interaction.

No interactions have been identified.

Special precautions for use

The cream should only be used for the treatment of herpes labialis and facial herpes. It is not recommended to apply the cream to mucous membranes, such as the oral cavity or eyes, and it must not be used for the treatment of genital herpes. Accidental contact of the cream with the eyes should be avoided.

Patients suffering from particularly severe or recurrent episodes of Herpes labialis should consult a physician. Patients with herpes infection should be advised to avoid transmitting the virus to others, especially when lesions are open (e.g., hands should be washed before and after applying the cream). The product is not recommended for immunocompromised individuals. Such patients should consult a physician regarding the treatment of any infection.

The medicinal product contains propylene glycol, which may cause skin irritation, and cetyl stearyl alcohol, which may cause local skin reactions (e.g., contact dermatitis).

Use during pregnancy or breastfeeding

This product should be used in pregnant or breastfeeding women only if, in the opinion of the physician, the benefit outweighs the potential risk. However, it should be noted that systemic absorption of acyclovir after topical application of the cream is very low.

Clinical studies have shown that the use of acyclovir in any formulation does not lead to an increased incidence of fetal developmental abnormalities.

Some clinical data indicate that acyclovir passes into breast milk following systemic administration. However, the amount of acyclovir that could be transferred to an infant during breastfeeding after topical application of this cream is negligible.

Clinical studies have shown that oral administration of acyclovir has no clinically significant effect on male fertility. Data regarding the effect of acyclovir on female fertility are lacking.

Ability to affect reaction speed when driving or operating machinery. No data available.

Method of administration and dosage.

The product is intended for external use only.

For adults and children aged 12 years and older

The cream should be applied 5 times daily at approximately 4-hour intervals, except during nighttime. It is important to start treatment as early as possible at the onset of infection, preferably during the prodromal stage or at the erythema stage. Treatment may also be initiated at later stages—papules or blisters.

Treatment should last at least 4 days. If healing has not occurred, treatment may be continued for up to 10 days. If symptoms persist after 10 days of treatment, the patient should consult a physician. Hands should be washed before and after applying the cream, and excessive rubbing or towel contact with affected areas should be avoided to prevent aggravation or transmission of infection.

Children. There is insufficient data on the safety of using the product in children under 12 years of age; therefore, use is recommended only for children aged 12 years and older.

Overdose. Adverse effects following oral or topical application of the entire contents of the tube are not expected due to minimal systemic exposure. In case of suspected overdose, medical advice should be sought.

Adverse Reactions.

Skin and connective tissue disorders

Uncommon (≥ 1/1000; < 1/100): transient burning or stinging pain after cream application, moderate drying and peeling of the skin, pruritus.

Rare (≥ 1/10000; < 1/1000): erythema, contact dermatitis after cream application (sensitivity testing has shown that these cases were most frequently associated with components of the cream base rather than with acyclovir).

Immune system disorders

Very rare (< 1/10000): immediate hypersensitivity reactions, including angioedema and urticaria.

Shelf life. 3 years.

Storage conditions. Store at a temperature not exceeding 25 ºC, in a place inaccessible to children. Do not freeze.

Packaging. 2 g (g) of cream in an aluminum foil tube with a screw plastic cap. One tube per cardboard box.

Availability. Over-the-counter (without prescription).

Manufacturer.

1. Glaxo Operations UK Limited, United Kingdom / Glaxo Operations UK Limited, United Kingdom

(manufacturing of the medicinal product, primary and secondary packaging, quality control, batch release)

1. Haleon CH S.a.r.l., Switzerland / Haleon CH S.a.r.l., Switzerland

(primary and secondary packaging, quality control, batch release)

Manufacturer's address and place of business.

1. Harmire Road, Barnard Castle, DL12 8DT, United Kingdom / Harmire Road, Barnard Castle, DL12 8DT, United Kingdom

2. Route de l’Etraz 2, Nyon, 1260, Switzerland / Route de l’Etraz 2, Nyon, 1260, Switzerland