What is the recommended dose of Valtrex (valacyclovir) for various indications?

Valacyclovir (Valtrex) Dosing Recommendations for Various Indications

The recommended dosage of valacyclovir (Valtrex) varies by indication, with 1 gram three times daily for 7 days for herpes zoster, 1 gram twice daily for 10 days for initial genital herpes episodes, and 2 grams twice daily for 1 day for cold sores. 1

Adult Dosing by Indication

Herpes Zoster (Shingles)

• Dose: 1 gram 3 times daily for 7 days 1
• Initiate at earliest sign or symptom of herpes zoster
• Most effective when started within 48 hours of rash onset
• Continue until all lesions are completely crusted over 2
• May extend beyond 7 days if lesions are not fully crusted 2

Genital Herpes

1. Initial Episode:

   • 1 gram twice daily for 10 days 1
   • Most effective when started within 48 hours of symptom onset

2. Recurrent Episodes:

   • 500 mg twice daily for 3 days 1
   • Alternative: 3-day course is equivalent to 5-day course in efficacy 3
   • Initiate at first sign or symptom of an episode

3. Suppressive Therapy:

   • Normal immune function: 1 gram once daily 1
   • For patients with ≤9 recurrences per year: 500 mg once daily 1
   • HIV-infected patients (CD4+ ≥100 cells/mm³): 500 mg twice daily 1

4. Reduction of Transmission:

   • 500 mg once daily for source partner (with ≤9 recurrences/year) 1

Cold Sores (Herpes Labialis)

• Dose: 2 grams twice daily for 1 day (12 hours apart) 1
• Initiate at earliest symptom (tingling, itching, or burning)

Chickenpox (Pediatric Patients)

• 20 mg/kg three times daily for 5 days (maximum 1 gram 3 times daily) 1
• For immunocompetent children aged 2 to <18 years

Renal Dosage Adjustments

For Creatinine Clearance 30-49 mL/min:

• Cold sores: No reduction
• Genital herpes (recurrent/suppressive): No reduction
• Herpes zoster: 1 gram every 12 hours 1

For Creatinine Clearance 10-29 mL/min:

• Cold sores: 1 gram every 24 hours
• Genital herpes (recurrent/suppressive): 500 mg every 24 hours
• Herpes zoster: 1 gram every 24 hours 1

For Creatinine Clearance <10 mL/min:

• Cold sores: 500 mg every 24 hours
• Genital herpes (recurrent/suppressive): 500 mg every 24 hours
• Herpes zoster: 500 mg every 24 hours 1

Special Populations

Hemodialysis Patients

• Administer recommended dose after hemodialysis
• Approximately one-third of acyclovir is removed during a 4-hour session 1

Immunocompromised Patients

• Higher doses and longer treatment durations may be necessary 2
• For HIV-infected patients, higher oral doses may be required 2

Clinical Pearls

• Valacyclovir may be taken without regard to meals 1
• Initiate treatment at earliest sign of symptoms for maximum effectiveness
• For herpes zoster, continue treatment until all lesions are completely crusted over 2
• Oral valacyclovir provides significantly better bioavailability than oral acyclovir, allowing less frequent dosing 4
• For patients with frequent recurrences (≥10 per year), 1 gram valacyclovir once daily is more effective than 500 mg once daily 5

Preparation of Oral Suspension

For pediatric patients who cannot take solid dosage forms:

• 25 mg/mL or 50 mg/mL suspension can be prepared from 500 mg tablets
• Store refrigerated (2-8°C)
• Discard after 28 days 1

Following these evidence-based dosing recommendations will optimize treatment outcomes while minimizing adverse effects for patients requiring valacyclovir therapy.