II. Indications
- Herpes Zoster (Shingles)
- Genital Herpes (initial, recurrent or prophylaxis)
- Herpes Labialis (Oral Herpes)
III. Mechanism
- See Acyclovir
IV. Dosing
-
Herpes Labialis (Cold Sores)
- Adults (and age >12 years): 2 grams orally every 12 hours for 1 day (2 doses)
-
Herpes Zoster (Shingles)
- Adult: 1 gram orally three times daily for 7 days
-
Genital Herpes
- Initial: 1 gram orally twice daily for 10 days
- Recurrent
- Take 500 mg orally twice daily for 3 days (FDA approved) OR
- Take 1000 mg orally daily for 5 days (off label)
- Prophylaxis (for up to 1 year)
- Immunocompetent (<9 episodes/year): 500 mg orally daily
- Immunocompetent (9 or more per year): 1000 mg orally daily
- HIV with CD4>100: 500 mg orally twice daily
-
Chicken Pox (immunocompetent)
- Age 2 to 12 years: 20 mg/kg/dose (max 1000 mg) orally three times daily for 5 days
-
Renal Dosing
- Reduce dose if eGFR <50 ml/min
V. Adverse Effects
- Nausea or Vomiting
- Headache
- Dizziness
-
Thrombotic Thrombocytopenic Purpura (rare)
- Has been associated with very high doses (8 g/day)
VI. Safety
- Pregnancy Category B
- Considered safe in Lactation
VII. Resources
VIII. References
Images: Related links to external sites (from Bing)
Related Studies
| 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 |
Ontology: valacyclovir (C0249458)
| Definition (NCI_NCI-GLOSS) | A substance that is being studied in the prevention of fungal, bacterial, and viral infections in patients undergoing donor stem cell transplantation with cells that are infected with cytomegalovirus. It belongs to the family of drugs called antivirals. |
| Definition (NCI) | The hydrochloride salt of the L-valyl ester of the antiviral drug acyclovir. Orally administered, valacyclovir is rapidly converted to acyclovir which inhibits viral DNA replication after further conversion to the nucleotide analog acyclovir triphosphate by viral thymidine kinase, cellular guanyl cyclase, and a number of other cellular enzymes. Acyclovir triphosphate competitively inhibits viral DNA polymerase; incorporates into and terminates the growing viral DNA chain; and inactivates viral DNA polymerase. The greater antiviral activity of acyclovir against herpes simplex virus (HSV) compared with varicella-zoster virus (VZV) is due to its more efficient phosphorylation by HSV thymidine kinase. |
| Definition (CSP) | used in the management of herpes simplex virus and varicella zoster virus infections and the prophylaxis of human cytomegalovirus infections. |
| Definition (PDQ) | A synthetic valyl ester derivative of acyclovir, the antiviral valacyclovir is an acyclovir prodrug that, after metabolization, inhibits viral DNA replication through interference with thymidine kinase. It is used in the management of herpes simplex and varicella zoster infections, as well as prophylactically for human cytomegalovirus infections. Check for "http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?id=257236&idtype=1" active clinical trials or "http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?id=257236&idtype=1&closed=1" closed clinical trials using this agent. ("http://nciterms.nci.nih.gov:80/NCIBrowser/ConceptReport.jsp?dictionary=NCI_Thesaurus&code=C28235" NCI Thesaurus) |
| Concepts | Pharmacologic Substance (T121) , Organic Chemical (T109) |
| MSH | C084555 |
| SnomedCT | 324820003, 96098007 |
| LNC | LP171646-5 |
| English | valaciclovir, valacyclovir, Valacyclovir product (product), Valaciclovir product (product), Valacyclovir, Valaciclovir, valacyclovir [Chemical/Ingredient], valACYclovir, L-Valine ester with 9-((2-hydroxyethoxy)methyl)guanine, VALACYCLOVIR, Valaciclovir product, Valacyclovir (substance), Valacyclovir product, Valaciclovir product (substance) |
| Spanish | valaciclovir (producto), producto con valaciclovir (producto), producto con valaciclovir, valaciclovir (sustancia), valaciclovir |
Ontology: Valtrex (C0592245)
| Concepts | Pharmacologic Substance (T121) , Organic Chemical (T109) |
| MSH | C084555 |
| English | Valtrex, valtrex |
