II. Indications

  1. Herpes Zoster (Shingles)
  2. Genital Herpes (initial, recurrent or prophylaxis)
  3. Herpes Labialis (Oral Herpes)

III. Mechanism

  1. See Acyclovir

IV. Dosing

  1. Herpes Labialis (Cold Sores)
    1. Adult: 2 grams orally every 12 hours for 1 day (2 doses)
  2. Herpes Zoster (Shingles)
    1. Adult: 1 gram orally three times daily for 7 days
  3. Genital Herpes
    1. Initial: 1 gram orally twice daily for 10 days
    2. Recurrent
      1. Take 500 mg orally twice daily for 3 days (FDA approved) OR
      2. Take 1000 mg orally daily for 5 days (off label)
    3. Prophylaxis (for up to 1 year)
      1. Immunocompetent (<9 episodes/year): 500 mg orally daily
      2. Immunocompetent (9 or more per year): 1000 mg orally daily
      3. HIV with CD4>100: 500 mg orally twice daily
  4. Renal Dosing
    1. Reduce dose if eGFR <50 ml/min

V. Adverse Effects

  1. Nausea or Vomiting
  2. Headache
  3. Dizziness
  4. Thrombotic Thrombocytopenic Purpura (rare)
    1. Has been associated with very high doses (8 g/day)

VI. Safety

  1. Pregnancy Category B
  2. Considered safe in Lactation

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Related Studies

Cost: Medications

valacyclovir (on 12/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing)
VALACYCLOVIR HCL 1 GRAM TABLET Generic $0.51 each
VALACYCLOVIR HCL 500 MG TABLET Generic $0.28 each
valtrex (on 9/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing)
VALTREX 1 GM CAPLET Generic $0.51 each
VALTREX 500 MG CAPLET Generic $0.28 each