Valacyclovir Dosing Recommendations

For suppressive therapy of recurrent genital herpes in HIV-infected persons, valacyclovir should be dosed at 500 mg twice daily. 1

Dosing for Different Clinical Scenarios

Initial episode: 1 gram twice daily for 10 days 2
Recurrent episodes: 500 mg twice daily for 3 days 2
Suppressive therapy:
- Immunocompetent patients: 1 gram once daily 2
- Immunocompetent patients with ≤9 recurrences/year: 500 mg once daily 2
- HIV-infected patients: 500 mg twice daily 1, 2
- For reduction of transmission: 500 mg once daily 2

2 grams twice daily for 1 day (taken 12 hours apart) 3, 2
Alternative regimen: 2 grams twice daily on Day 1, then 1 gram twice daily on Day 2 3

Valacyclovir requires dose adjustment in patients with renal impairment:

Creatinine Clearance (mL/min)	Genital Herpes Recurrent	Genital Herpes Suppressive	HIV-Infected Suppressive
≥50 (normal)	500 mg every 12 hours	1 gram every 24 hours	500 mg every 12 hours
30-49	No reduction	No reduction	No reduction
10-29	500 mg every 24 hours	500 mg every 24 hours	500 mg every 24 hours
<10	500 mg every 24 hours	500 mg every 24 hours	500 mg every 24 hours

For hemodialysis patients, administer the recommended dose after hemodialysis 2.

Valacyclovir has significantly better oral bioavailability than oral acyclovir, allowing for less frequent dosing 4, 5
Daily suppressive therapy reduces the frequency of genital herpes recurrences by ≥75% among patients with frequent recurrences 1
Therapy for recurrent episodes should be initiated at the earliest sign of prodrome or genital lesions for maximum benefit 1
Short-course therapy (1-3 days) should not be used in HIV-infected patients 1
Valacyclovir 500 mg once daily appears less effective than other valacyclovir dosing regimens in patients with very frequent recurrences (≥10 episodes per year) 1

No laboratory monitoring is needed in patients receiving episodic or suppressive therapy unless the patient has substantial renal impairment 1
Treatment failure should be suspected if lesions do not begin to resolve within 7-10 days after initiation of therapy 1
After 1 year of continuous suppressive therapy, consider discontinuing to reassess recurrence frequency 1

Valacyclovir is occasionally associated with nausea or headache 1
Thrombotic thrombocytopenic purpura/hemolytic uremic syndrome has been reported among HIV-infected patients treated with high-dose (8 grams/day) valacyclovir but has not been reported at doses used for therapy of HSV infection 1

Remember that valacyclovir can be given without regard to meals, and therapy should be initiated at the earliest symptom for maximum effectiveness 2.