Acyclovir Dosing for Cold Sores
For cold sores (oral herpes), the recommended dosing options for acyclovir are: 400 mg orally three times daily for 5 days, 200 mg orally five times daily for 5 days, or 800 mg orally twice daily for 5 days. 1, 2
Standard Treatment Regimens
- Treatment should be initiated during the prodrome or within 2 days of onset of lesions for maximum effectiveness 2
- Three equally effective oral acyclovir regimens for episodic treatment of cold sores:
Clinical Considerations
- Early treatment initiation is crucial - starting therapy at the first sign of symptoms (tingling, burning) provides the greatest benefit 2
- Oral acyclovir is significantly more effective than topical formulations for treating cold sores 2
- Most immunocompetent patients with recurrent disease experience limited benefit from therapy 2
- Acyclovir neither eradicates latent virus nor affects subsequent risk, frequency, or severity of recurrences after discontinuation 2
Special Populations
Immunocompromised Patients
- HIV-infected or otherwise immunocompromised patients may require higher doses 1
- For immunocompromised patients, recommended dosing: acyclovir 400 mg orally three to five times daily until clinical resolution 1
- For severe cases in immunocompromised patients, intravenous therapy may be required: acyclovir 5-10 mg/kg IV every 8 hours 1
Frequent Recurrences
- For patients with more than six recurrences per year, suppressive therapy may be considered 3
- Suppressive dosing: acyclovir 400 mg orally twice daily 1
Practical Advice
- Patients should avoid close contact while they have active lesions to prevent transmission 2
- Treatment should be initiated as soon as symptoms appear for best results 2, 3
- Allergic reactions to acyclovir are infrequent 1
- The 800 mg twice daily regimen may offer better compliance due to reduced frequency of dosing 1, 2