Typical Duration for Herpes Simplex Infections
For initial episodes of genital herpes, acyclovir is recommended for 7-10 days, typically starting at 400 mg orally three times daily.[1] Recurrent genital herpes treatment lasts 5 days at 400 mg three times daily.[1] Oral herpes (cold sores) episodes are treated for 5-10 days with 200-400 mg five times daily.[1]
Shingles (Herpes Zoster) Treatment Length
Acyclovir treats shingles for 7-10 days at 800 mg orally five times daily, ideally started within 72 hours of rash onset to reduce pain and duration.[1][2]
Chickenpox Duration
In children and adults with chickenpox, treatment is 5 days at 20 mg/kg (up to 800 mg) four times daily for kids or 800 mg four to five times daily for adults.[1]
Herpes Encephalitis or Severe Cases
Intravenous acyclovir for herpes encephalitis runs 14-21 days at 10 mg/kg every 8 hours, adjusted for kidney function.[1][2]
Suppression Therapy Timeline
For frequent genital herpes recurrences (≥6 per year), long-term suppression uses 400 mg orally twice daily, often indefinitely or reassessed yearly.[1] Prophylaxis post-transplant or in immunocompromised patients can last months to years.[2]
Factors Affecting Duration
Dosage and length shorten for kidney impairment—reduce by 50% if creatinine clearance is 10-25 mL/min.[1] Always complete the full course to prevent resistance, even if symptoms improve.[2] Consult a doctor for personalized adjustments based on immune status or pregnancy.
[1]: CDC Sexually Transmitted Infections Treatment Guidelines
[2]: UpToDate: Acyclovir Dosing and Administration