Generic
Acyclovir (Topical)
7 brands available in the market
At a glance
Acyclovir (Topical) is an antiviral cream used for the treatment of skin infections caused by herpes simplex virus (herpes labialis/cold sores). It prevents viral multiplication in skin cells and clears the infection.
Description
Acyclovir (Topical) is an antiviral cream active against herpes simplex virus types 1 and 2 and varicella-zoster virus. It is converted by viral thymidine kinase to acyclovir monophosphate, which is further converted to diphosphate and active triphosphate by cellular enzymes. This active form inhibits viral DNA synthesis and replication by interfering with viral DNA polymerase and incorporating into viral DNA. It is for external use only.
Indications
Initial and recurrent labial herpes (cold sores/herpes labialis) and genital herpes simplex infections (treatment should begin as early as possible).
Therapeutic class
Topical Antiviral Preparations
Pharmacological class
Antiviral (Nucleoside Analog)
Pharmacology
Acyclovir is a synthetic purine derivative that exerts antiviral effects on Herpes simplex virus (HSV) and Varicella zoster virus by interfering with DNA synthesis and inhibiting viral replication. In herpes-infected cells, acyclovir's antiviral activity depends on intracellular conversion to acyclovir triphosphate. Acyclovir is converted to acyclovir monophosphate primarily via virus-coded thymidine kinase; the monophosphate is phosphorylated to diphosphate via cellular guanylate kinase and then to triphosphate via other cellular enzymes, which is the pharmacologically active form. Percutaneous absorption of acyclovir is minimal following topical application to intact skin.
Mechanism of action
Acyclovir is converted to acyclovir triphosphate inside virus-infected cells, which inhibits viral DNA polymerase and incorporates into viral DNA, stopping viral DNA replication.
Dosage
Adults and children over 12 years:
- Apply cream to lesions 5 times daily (approximately every 4 hours)
- Continue treatment for 5-10 days
- Initiate treatment as early as possible after onset of signs and symptoms
Administration
- For external use only (do not use in eyes, mouth, nose, or vagina)
- Wash hands before and after application
- Clean and dry the affected area before application
- Apply a thin layer of cream to the lesions
- Wear loose-fitting clothing (to avoid irritation to the lesion)
- Do not touch sores unnecessarily with hands or towels (to avoid spreading infection)
Missed dose
If you miss a dose, apply it as soon as you remember. If it is almost time for your next dose, skip the missed dose and continue with your regular schedule. Do not double the dose.
Side effects
Common side effects (<1%):
- Dry lips
- Desquamation (skin peeling)
- Dry skin
- Cracked lips
- Burning sensation on skin
- Pruritus (itching)
- Flakiness of skin
- Stinging sensation on skin
Precautions & warnings
- Apply only to external aspects of lips and face
- Do not use in eyes, inside the mouth, or inside the nose
- Consult doctor if symptoms do not improve after 10 days
- Efficacy not established in immunocompromised patients
- May cause irritation or contact dermatitis at application site
Contraindications
Hypersensitivity to acyclovir, valacyclovir, or any component of the formulation.
Drug interactions
No interactions have been identified with topical or systemic administration of other drugs. Systemic drug interactions are unlikely due to minimal systemic absorption.
Food interactions
No food interactions (topical application).
Use in pregnancy
Pregnancy Category: B. Use during pregnancy only if potential benefit justifies potential risk to the fetus.
Pregnancy Category: B — always consult a doctor before taking during pregnancy.
Use in lactation
Use with caution in nursing mothers.
Pediatric use
Under 12 years: Safety and efficacy have not been established.
12-17 years: Adult dose applies (safety profile similar to adults).
Geriatric use
Clinical studies did not include sufficient subjects aged 65 and over; however, reported clinical experience has not identified differences in responses between elderly and younger patients.
Renal / hepatic impairment
No dose adjustment needed for topical use (minimal systemic absorption).
Overdose effects
Topical overdose is unlikely; excessive application may cause skin irritation.
Storage conditions
Store at room temperature between 20°C-25°C.
Chemical structure
Acyclovir 5% Topical Cream