From the Guidelines
Valacyclovir is typically prescribed at 1 gram twice daily for 7-10 days for initial genital herpes outbreaks, and 500 mg twice daily for 3-5 days for recurrent episodes, with dosing adjustments needed for patients with kidney impairment, as recommended by the most recent guidelines 1. The medication works best when started at the earliest signs of an outbreak, ideally within 24-48 hours of symptom onset.
- For oral herpes (cold sores), the standard dosage is 2 grams twice in one day, taken 12 hours apart.
- For suppressive therapy to prevent recurrences, 500-1000 mg once daily is recommended, with the specific dosage depending on the patient's kidney function, as outlined in the 2014 clinical practice guideline for the management of chronic kidney disease in patients infected with HIV 1. Valacyclovir is a prodrug that converts to acyclovir in the body, which then inhibits viral DNA replication by targeting the herpes virus DNA polymerase.
- This medication should be taken with plenty of water, and patients should maintain adequate hydration throughout treatment.
- While valacyclovir reduces symptoms and viral shedding, it does not cure herpes infections, so patients should be counseled about the chronic nature of the condition and the importance of safe sex practices even during treatment, as emphasized in the guidelines for prevention and treatment of opportunistic infections in HIV-infected adults and adolescents 1. Key considerations for dosing adjustments in patients with kidney impairment include:
- CrCl 30–49 mL/min: 500 mg–1 g po q12h
- CrCl 10–20 mL/min: 500-1 g mg po q24h
- CrCl <10 mL/min: 500 mg po q24h, as specified in the 2014 guideline 1.
From the FDA Drug Label
2 DOSAGE AND ADMINISTRATION
... 2.1 Adult Dosing Recommendations ... Genital Herpes Initial Episode: The recommended dosage of VALTREX for treatment of initial genital herpes is 1 gram twice daily for 10 days. Recurrent Episodes: The recommended dosage of VALTREX for treatment of recurrent genital herpes is 500 mg twice daily for 3 days ... Herpes Zoster The recommended dosage of VALTREX for treatment of herpes zoster is 1 gram 3 times daily for 7 days ... 2.2 Pediatric Dosing Recommendations ... Cold Sores (Herpes Labialis) The recommended dosage of VALTREX for the treatment of cold sores in pediatric patients aged greater than or equal to 12 years is 2 grams twice daily for 1 day taken 12 hours apart. ...
The dosage and treatment plan for Valacyclovir for herpes simplex virus infections is as follows:
- Initial Genital Herpes: 1 gram twice daily for 10 days
- Recurrent Genital Herpes: 500 mg twice daily for 3 days
- Cold Sores (Herpes Labialis): 2 grams twice daily for 1 day taken 12 hours apart for adults and pediatric patients aged greater than or equal to 12 years
- Herpes Zoster: 1 gram 3 times daily for 7 days 2
From the Research
Dosage and Treatment Plan for Valacyclovir
- The recommended dosage of valacyclovir for the suppression of genital herpes recurrences in immunocompetent individuals is 500 mg to 1000 mg daily 3.
- For the treatment of first-episode genital herpes, valacyclovir can be administered at a dose of 1000 mg twice daily for 10 days, which is as effective as acyclovir 200 mg five times daily 4.
- In the treatment of herpes zoster, valacyclovir is more effective than acyclovir and equally effective as famciclovir in hastening the healing of zoster-associated pain and postherpetic neuralgia 5.
- Valacyclovir is also approved for a 3-day course in the episodic treatment of recurrent genital herpes and for once-daily dosing for suppressive therapy 5.
Efficacy and Safety
- Valacyclovir has been shown to be effective in reducing the duration of viral shedding, hastening lesion healing, and decreasing lesion-associated pain in patients with genital herpes 6, 4.
- Valacyclovir is well tolerated, with a similar tolerability profile to acyclovir or placebo 6, 4.
- However, high-dose valacyclovir therapy (8 g/day) for prolonged periods has been associated with a potentially fatal thrombotic microangiopathy-like syndrome in some immunocompromised patients 3.
Comparison with Other Antiviral Agents
- Valacyclovir has been compared with acyclovir and famciclovir in several studies, and has been shown to be at least as effective as these agents in the treatment of genital herpes and herpes zoster 6, 5, 4.
- Valacyclovir has the advantage of a more convenient dosing regimen and the potential for improved compliance compared to acyclovir 4.