Virux

Indications

Virux cream, an antiviral medication containing acyclovir, is prescribed for the treatment of recurrent herpes labialis (cold sores) in immunocompetent adults and adolescents aged 12 and above.

Pharmacology

Acyclovir, an antiviral agent, works against herpes simplex virus (HSV) by inhibiting its DNA polymerase. This synthetic purine nucleoside analogue hinders HSV-1 and HSV-2 through its affinity for the viral enzyme thymidine kinase (TK). Acyclovir triphosphate, formed through cellular conversion, disrupts viral DNA replication by competitive inhibition of viral DNA polymerase, incorporation into the DNA chain, and inactivation of viral DNA polymerase.

Dosage & Administration

Apply acyclovir cream five times daily for four days, starting at the earliest signs of herpes labialis symptoms. Dosage for adolescents aged 12 and older mirrors that of adults.

Interactions

No interactions have been observed with either topical or systemic use of Virux cream due to minimal systemic absorption.

Contraindications

Acyclovir cream should not be used by individuals with known hypersensitivity to acyclovir, valacyclovir, or any components of the formulation.

Side Effects

Common adverse reactions at the application site include dry lips, skin desquamation, dryness, cracking, burning, itching, flakiness, and stinging. Discontinuation due to adverse events is rare.

Pregnancy & Lactation

Pregnancy Category B. Use during pregnancy should be based on risk-benefit assessment. The excretion of topically applied acyclovir in breast milk is unknown, with minimal systemic exposure.

Precautions & Warnings

Virux cream is intended for external application only on affected areas of the lips and face. Avoid mucous membrane contact. Caution is advised regarding potential irritation and contact. Its efficacy in immunocompromised patients is undetermined.

Use in Special Populations

Pediatric Use: Safety profile in adolescents aged 12 to 17 is similar to adults, but efficacy and safety in those under 12 remain unestablished. Geriatric Use: Limited data in subjects over 65 suggest no significant differences in response compared to younger individuals.

Therapeutic Class

Topical antiviral preparations

Storage Conditions

Store Virux cream at room temperature, between 20°C to 25°C.