Aciclovir (Topical): Uses, Dosage, Side Effects & Clinical Use | MedexInfo

Aciclovir (Topical)

Rx / OTC

Therapeutic ClassAntiviral

Common Dose5% Cream

RouteTopical

PregnancyCategory B / C (use if clearly needed)

Indications ▼

Cold sores (Herpes labialis)

Herpes simplex virus skin infections

Prophylactic use in immunocompromised patients (limited)

Mechanism & Pharmacokinetics ▼

Mechanism: Guanosine analogue that inhibits viral DNA polymerase after phosphorylation by viral thymidine kinase, selectively preventing viral replication.

Pharmacokinetics: Minimal systemic absorption. Concentrates in skin lesions. Metabolized minimally in liver; excreted unchanged in urine in trace amounts.

Dosage & Administration ▼

Patient Group	Dose	Frequency / Duration
Adults & Adolescents	Apply 5% cream	5 times daily for 4–5 days
Children (≥2 years)	Apply 5% cream	5 times daily for 4–5 days

Side Effects ▼

Local irritation, burning, or stinging at application site

Itching or mild erythema

Rare: Hypersensitivity reactions, rash beyond application site

Contraindications ▼

Hypersensitivity to aciclovir or valaciclovir

Open or severely inflamed skin lesions (consult physician)

Drug Interaction ▼

Minimal systemic absorption, so drug interactions are rare

Caution with nephrotoxic drugs if systemic absorption occurs

Pregnancy & Lactation ▼

Topical use generally considered safe if clearly needed

Compatible with breastfeeding (minimal systemic absorption)

Clinical / Research Summary ▼

Antiviral Efficacy: Aciclovir topical has demonstrated potent activity against herpes simplex virus (HSV-1 and HSV-2), effectively reducing viral replication and lesion duration.

Clinical Studies: Multiple randomized controlled trials show that 5% aciclovir cream applied 5 times daily shortens healing time of cold sores by 1–2 days compared to placebo.

Prophylactic Use: Topical aciclovir may decrease the frequency of recurrent herpes labialis in patients with frequent outbreaks.

Safety Profile: Well tolerated with minimal local irritation; systemic absorption is negligible, making it safe for immunocompetent adults and children.

Combination Therapy: Often used alongside systemic antivirals in severe or widespread cases, though topical alone suffices for localized lesions.

Research Insights: Recent studies suggest that early initiation (within 24 hours of symptom onset) maximizes efficacy. Ongoing trials are evaluating newer formulations for faster absorption and reduced application frequency.

Patient Counseling Points ▼

Wash hands before and after applying cream

Apply to affected area only

Complete full course even if lesions improve

Avoid contact with eyes or mucous membranes

Storage & Handling ▼

Store at 20–25°C, protect from light

Keep out of reach of children

Do not freeze

Brand Names (Bangladesh & Global) ▼

Bangladesh (Local Brands):

Zovirax Topical Aciclovir Cream Virac Acivir Aciclovir 5%

Global / International Brands:

Zovirax Topical Sitavig Avaclyr Cream Viraloid Aciclovir 5% Cream

Medical Disclaimer: This clinical summary is for educational purposes only. Always consult a qualified healthcare provider before use.

Reference Hubs:

• Drug Class: Antivirals • Conditions: Herpes Labialis & Skin Infections • Pathway: Viral DNA Replication