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Related to valaciclovir: Valtrex

valacyclovir hydrochloride (valaciclovir (UK))

Apo-Valacyclovir, Valtrex

Pharmacologic class: Acyclic purine nucleoside analog

Therapeutic class: Antiviral

Pregnancy risk category B


Rapidly converts to acyclovir, which interferes with viral DNA synthesis and replication


Caplets: 500 mg, 1 g

Indications and dosages

Herpes zoster (shingles)

Adults: 1 g P.O. t.i.d. for 7 days. Therapy should begin at first sign or symptom of herpes zoster, within 48 hours of onset of zoster rash.

Genital herpes

Adults: For initial episode, 1 g P.O. b.i.d. for 10 days. For recurrent episodes, 500 mg P.O. b.i.d. for 3 days. For chronic suppression, 1 g P.O. daily for no more than 1 year; in patients with history of fewer than nine yearly recurrences, 500 mg P.O. daily for no more than 1 year.

To reduce risk of genital herpes in immunocompetent patients

Adults: 500 mg P.O. daily for source partner, along with counseling regarding safe sex practices

Herpes labialis

Adults: 2 g b.i.d. for 1 day taken 12 hours apart. Begin therapy at first symptom of lesion.

Dosage adjustment

• Renal impairment

Off-label uses

• Cytomegalovirus prophylaxis


• Hypersensitivity to drug, its components, or acyclovir


Use cautiously in:

• renal impairment, concurrent use of nephrotoxic drugs, inadequately hydrated patients

• elderly patients

• pregnant or breastfeeding patients

• children.


• Be aware that therapy may be ineffective if begun more than 72 hours after initial genital herpes outbreak, or more than 24 hours after symptom onset in herpes recurrence.

Adverse reactions

CNS: headache, dizziness, depression, agitation, hallucinations, confusion, encephalopathy

GI: nausea, vomiting, diarrhea, abdominal pain

GU: dysmenorrhea, acute renal failure

Hematologic: anemia, leukopenia, thrombocytopenia, hemolytic uremic syndrome/thrombotic thrombocytopenic purpura/(HUS/TTP)

Musculoskeletal: joint pain

Other: hypersensitivity reaction


Drug-drug. Cimetidine, probenecid: increased valacyclovir blood level

Drug-diagnostic tests. Alanine aminotransferase, alkaline phosphatase, aspartate aminotransferase: increased levels

Patient monitoring

Monitor CBC. Stay alert for signs and symptoms of blood dyscrasias. Discontinue drug if clinical signs and symptoms and laboratory findings consistent with HUS/TTP occur.

• Assess liver and kidney function tests.

Patient teaching

• Inform patient that herpes transmission can occur even when he is asymptomatic.

• Tell patient and significant other that no cure exists for herpes. Urge them to practice safe sex.

• Inform pregnant patient of risk of neonatal herpes infection.

• Instruct pregnant patient or female of childbearing age to tell health care provider that she has herpes. After delivery, tell her to inform neonatal care providers.

Instruct patient to promptly report unusual bleeding or bruising, urinary changes, or serious adverse CNS reactions.

• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and tests mentioned above.

McGraw-Hill Nurse's Drug Handbook, 7th Ed. Copyright © 2013 by The McGraw-Hill Companies, Inc. All rights reserved


An antiviral drug used to treat genital herpes and SHINGLES. Like ACICLOVIR, the drug is a DNA polymerase inhibitor. Research has shown that a daily dose of 500 mg of this drug reduces the risk of transmission of genital herpes by 75 percent. A brand name is Valtrex.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005
References in periodicals archive ?
Valaciclovir. Valaciclovir has also been used with success in preventing CMV infection in KTR [111].
Aciclovir, valaciclovir and valganciclovir inhibit the enzyme responsible for copying viral DNA in an infected cell.
The firm also launched nine new products last year, including Valaciclovir and Imipenem + Cilastatin.
In the Sullivan et al study7 (which showed no benefit of adding aciclovir to steroids) the mean HouseBrackmann grade was 3.6, whereas the mean score was 4.3 in the Hato et al study, which reported a significant benefit of adding valaciclovir (97 versus 90 percent).21
standard-dose valaciclovir (500 mg daily), and those receiving standard- vs.
To assess whether standard and/or high doses of acidovir and valaciclovir affect these subclinical periods of HSV reactivation, they enrolled participants between November 2006 and July 2010 into the three studies, each with a 4- to 7-week initial treatment period, followed by a 1-week washout period, followed by crossover to the other treatment for an additional 4-7 weeks.
According to IMS Health, Valaciclovir had US sales of approximately USD1.5bn (EUR1.06m) for the 12 months ending 31 December 2010.
penciclovir, valaciclovir, famciclovir, and ganciclovir and others) have been approved for treatment of HSV-1 infections worldwide (Galasso et al., 1997; Leung and Sacks, 2000; Brady and Bernstein, 2004).
Rara vez requiere tratamiento, por ello, se aconseja, cuando al paciente le cause incomodidades o molestias de tipo estetico o funcional, administrar antifungicos para impedir la sobreinfeccion por Candida, y aciclovir y valaciclovir para evitar la reproduccion del virus y lograr la resolucion clinica de la leucoplasia.
The effect of valaciclovir on cytomegalovirus viremia and viruria detected by polymerase chain reaction in patients with advanced human immunodeficiency virus disease: AIDS ClinicalTrials Group Protocol 204/Glaxo Wellcome 123-014 International CMV Prophylaxis Study Group.