valacyclovir hydrochloride (valaciclovir (UK))

Apo-Valacyclovir, Valtrex

Pharmacologic class: Acyclic purine nucleoside analog

Therapeutic class: Antiviral

Pregnancy risk category B

Action

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

Availability

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

Contraindications

• Hypersensitivity to drug, its components, or acyclovir

Precautions

Use cautiously in:

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

• elderly patients

• pregnant or breastfeeding patients

• children.

Administration

• 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

Interactions

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.

Valtrex

(văl′trĕks′)

A trademark for the drug valacyclovir hydrochloride.

Valtrex

A brand name for VALACICLOVIR.

Mentioned in

References in periodicals archive

Boston- and Toronto-based BPG Werks, creators of the innovative all-terrain dual tracked vehicle (DTV) called the Shredder, have harnessed the exceptional durability and wear capabilities of a high-performance polymer from Valtrex to construct a robust and efficient overmoulded steel drive shaft segment gear.

Victrex input for DTV

Presently, acyclovir (Zovirax; GlaxoSmithKline Pharmaceuticals, Research Triangle Park, NC, USA) and valacyclovir (Valtrex; GlaxoSmithKline Pharmaceuticals, Research Triangle Park, NC, USA) have both been shown to be equally efficacious in prevention and treatment of HSV [139].

Oral complications and management strategies for patients undergoing cancer therapy

In this 60-patient study, 53% of participants assigned to valacy-clovir (Valtrex) exhibited a clinically meaningful improvement in cognitive function, defined as at least a 10-point gain over baseline on the Repeatable Battery for the Assessment of Neurological Status (RBANS), compared with 14% in the placebo arm, Dr.

Drug improves cognition in comorbid bipolar, HSV-1

Acyclovir (Zovirax), valacyclovir (Valtrex) and famciclovir (Famvir) are all prescription antiviral drugs that are effective in treating genital herpes.

Genital herpes

The current standard of care for these infections is the use of oral nucleoside analogues, such as valacyclovir (Valtrex).

Alternative therapy for HSV-2 studied

This figure excludes pandemic flu-related products Avandia (which has been withdrawn from the market) and Valtrex (facing severe generic competition).

COMPANY FOCUS: GLAXOSMITHKLINE

GSK said underlying sales, which exclude sales of scrapped diabetes blockbuster Avandia, pandemic flu vaccines and antiviral drug Valtrex, rose five per cent in the quarter.

Glaxo eyes boost from new products; business Business briefing

("It probably smells like Taco Bell and Valtrex," says a friend of a friend.)

Upstaged

Medco saw its generic dispensing rate climb 3.4% to 67.5% in 2009-a year when blockbuster drugs like Prevacid, Topamax, Valtrex and Adder-all XR went generic.

Savings in a bottle: generic pharmaceuticals resulted in nearly $140 billion in savings to the U.S. health care system in 2009. What are health plans doing to drive even further savings of these growing medications?

Glaxo's earnings slipped 1%, hit by the cost of writing off stocks of Avandia and increased generic competition for herpes drug Valtrex, although the results topped estimates.

Glaxo, Lilly Q3 sales slip; Novartis shines

Nucleoside analogues, including valacyclovir (Valtrex) and famciclovir (Famvir) (both Category B), pose little risk to mother and fetus.

ENT complaints in pregnancy. Part 2: the ear and the throat: did you know that laryngopharyngeal reflux is distinct from GERD--and becomes worse during pregnancy? That the thyroid enlarges in half of gravidas? That some pregnant women experience changes to their voice?