pharmacopeia
GET
/api/v1/drug/valacyclovir
2D structure
2-[(2-amino-6-oxo-1H-purin-9-yl)methoxy]ethyl (2S)-2-amino-3-methylbutanoate
SMILES CC(C)[C@@H](C(=O)OCCOCN1C=NC2=C1N=C(NC2=O)N)N
InChIKey HDOVUKNUBWVHOX-QMMMGPOBSA-N

Mechanism of action

Sourced from openFDA

Valacyclovir is an antiviral drug active against α-herpes viruses [see Microbiology (12.4) ].

DNA Polymerase

Indications

Sourced from openFDA
  • Valacyclovir tablets are a deoxynucleoside analogue DNA polymerase inhibitor indicated for: Adult Patients ( 1.1 ) Cold Sores (Herpes Labialis) Genital Herpes Treatment in immunocompetent patients (initial or recurrent episode) Suppression in immunocompetent or HIV-1–infected patients Reduction of transmission Herpes Zoster Pediatric Patients ( 1.2 ) Cold Sores (Herpes Labialis) Chickenpox Limitations of Use ( 1.3 ) The efficacy and safety of valacyclovir tablets have not been established in immunocompromised patients other than for the suppression of genital herpes in HIV-1–infected patients. 1.1 Adult Patients Cold Sores (Herpes Labialis) Valacyclovir tablets are indicated for treatment of cold sores (herpes labialis).ICD-10: A60.9, B00.9, B02.9, B20

Contraindications

Sourced from openFDA
  • Valacyclovir tablets are contraindicated in patients who have had a demonstrated clinically significant hypersensitivity reaction [e.g., anaphylaxis, severe cutaneous adverse reactions (SCARs)] to valacyclovir, acyclovir, or any component of the formulation [see Warnings and Precautions (5.4) , Adverse Reactions (6.3) ] . Hypersensitivity to valacyclovir (e.g., anaphylaxis), acyclovir, or any component of the formulation.contraindicated

Dosage & administration

Sourced from openFDA

Valacyclovir tablets may be given without regard to meals. Valacyclovir oral suspension (25 mg/mL or 50 mg/mL) may be prepared extemporaneously from 500-mg valacyclovir tablets for use in pediatric patients for whom a solid dosage form is not appropriate [see Dosage and Administration (2.3) ] . Adult Dosage ( 2.1 ) Cold Sores 2 grams every 12 hours for 1 day Genital Herpes Initial episode 1 gram twice daily for 10 days Recurrent episodes 500 mg twice daily for 3 days Suppressive therapy Immunocompetent patients 1 gram once daily Alternate dose in patients with less than or equal to 9 recurrences/year 500 mg once daily HIV-1–infected patients 500 mg twice daily Reduction of transmission 500 mg once daily Herpes Zoster 1 gram 3 times daily for 7 days Pediatric Dosage ( 2.2 ) Cold Sores (aged greater than or equal to 12 years) 2 grams every 12 hours for 1 day Chickenpox (aged 2 to less than 18 years) 20 mg/kg 3 times daily for 5 days; not to exceed 1 gram 3 times daily Valacyclovir oral suspension (25 mg/mL or 50 mg/mL) can be prepared from the 500 mg valacyclovir tablets. ( 2.3 ) 2.1 Adult Dosing Recommendations Cold Sores (Herpes Labialis) The recommended dosage of valacyclovir tablets for treatment of cold sores is 2 grams twice daily for 1 day taken 12 hours apart. Therapy should be initiated at the earliest symptom of a cold sore (e.g., tingling, itching, or burning). Genital Herpes Initial Episode The recommended dosage of valacyclovir tablets for treatment of initial genital herpes is 1 gram twice daily for 10 days.

Warnings & precautions

Sourced from openFDA

Thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS): Has occurred in patients with advanced HIV-1 disease and in allogenic bone marrow transplant and renal transplant patients receiving 8 grams per day of valacyclovir tablets in clinical trials. Discontinue treatment if clinical symptoms and laboratory findings consistent with TTP/HUS occur. ( 5.1 ) Acute renal failure: May occur in elderly patients (with or without reduced renal function), patients with underlying renal disease who receive higher-than-recommended doses of valacyclovir tablets for their level of renal function, patients who receive concomitant nephrotoxic drugs, or inadequately hydrated patients. Use with caution in elderly patients and reduce dosage in patients with renal impairment. ( 2.4 , 5.2 ) Central nervous system adverse reactions (e.g., agitation, hallucinations, confusion, and encephalopathy): May occur in both adult and pediatric patients (with or without reduced renal function) and in patients with underlying renal disease who receive higher-than-recommended doses of valacyclovir tablets for their level of renal function. Elderly patients are more likely to have central nervous system adverse reactions. Use with caution in elderly patients and reduce dosage in patients with renal impairment.

Adverse reactions

Sourced from openFDA

The following serious adverse reactions are discussed in greater detail in other sections of the labeling: Thrombotic Thrombocytopenic Purpura/Hemolytic Uremic Syndrome [see Warnings and Precautions (5.1) ]. Acute Renal Failure [see Warnings and Precautions (5.2) ] . Central Nervous System Effects [see Warnings and Precautions (5.3) ] . Severe Cutaneous Adverse Reactions [see Warnings and Precautions (5.4) ] . The most common adverse reactions reported in at least 1 indication by greater than 10% of adult subjects treated with valacyclovir tablets and observed more frequently with valacyclovir tablets compared with placebo are headache, nausea, and abdominal pain. The only adverse reaction reported in greater than 10% of pediatric subjects aged less than 18 years was headache. The most common adverse reactions reported in at least one indication by greater than 10% of adult subjects treated with valacyclovir tablets and more commonly than in subjects treated with placebo are headache, nausea, and abdominal pain. ( 6.1 ) The only adverse reaction occurring in greater than 10% of pediatric subjects aged less than 18 years was headache. ( 6.2 ) To report SUSPECTED ADVERSE REACTIONS, contact Mylan at 1-877-446-3679 (1-877-4-INFO-RX) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

Use in specific populations

Sourced from openFDA

8.1 Pregnancy Risk Summary Clinical data over several decades with valacyclovir and its metabolite, acyclovir, in pregnant women, have not identified a drug associated risk of major birth defects. There are insufficient data on the use of valacyclovir regarding miscarriage or adverse maternal or fetal outcomes (see Data ) . There are risks to the fetus associated with untreated herpes simplex during pregnancy (see Clinical Considerations ). In animal reproduction studies, no evidence of adverse developmental outcomes was observed with valacyclovir when administered to pregnant rats and rabbits at system exposures (AUC) 4 (rats) and 7 (rabbits) times the human exposure at the maximum recommended human dose (MRHD) (see Data ) . The estimated background risk of major birth defects and miscarriage for the indicated populations is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.

Pharmacokinetics

Sourced from openFDA
Metabolism
The pharmacokinetics of valacyclovir and acyclovir after oral administration of valacyclovir tablets have been investigated in 14 volunteer trials involving 283 adults and in 3 trials involving 112 pediatric subjects aged 1 month to less than 12 years. Pharmacokinetics in Adults Absorption and Bioavailability After oral administration, valacyclovir hydrochloride is rapidly absorbed from the gastrointestinal tract and nearly completely converted to acyclovir and L -valine by first-pass intestinal and/or hepatic metabolism.

Overdosage

Sourced from openFDA

Caution should be exercised to prevent inadvertent overdose [see Use in Specific Populations (8.5 , 8.6) ] . Precipitation of acyclovir in renal tubules may occur when the solubility (2.5 mg/mL) is exceeded in the intratubular fluid. In the event of acute renal failure and anuria, the patient may benefit from hemodialysis until renal function is restored [see Dosage and Administration (2.4) ] .

Approval history

Sourced from openFDA
  • Jun 23, 1995NDANDA020487Glaxosmithkline
  • Jan 31, 2007ANDAANDA076588Sun Pharm Inds Ltd
  • May 24, 2010ANDAANDA078518Mylan Pharms Inc
  • May 24, 2010ANDAANDA079012Rising
  • May 24, 2010ANDAANDA090682Aurobindo Pharma
  • Apr 3, 2012ANDAANDA201506Jubilant Generics
  • Apr 8, 2015ANDAANDA203047Hetero Labs Ltd V
  • Mar 18, 2020ANDAANDA209553Yiling

FAERS reports

View JSON
Reference statistics only. FAERS reports are voluntarily submitted and are not incidence rates, safety signals, or causal evidence. Counts reflect reporting volume — how often a reaction was reported, not how often it occurs. For decision-grade use, consult openFDA and the FAERS Public Dashboard directly.
68,551 total reports matchedLatest report Share = reports listing the reaction ÷ total matched reports. Rows can sum to >100% because a single report often lists multiple reactions.
  1. 1Fatigue4,2266.2%
  2. 2Drug Ineffective3,8955.7%
  3. 3Nausea3,8925.7%
  4. 4Off Label Use3,7225.4%
  5. 5Diarrhoea3,5545.2%
  6. 6Headache2,8864.2%
  7. 7Pyrexia2,7033.9%
  8. 8Pain2,6543.9%
  9. 9Pneumonia2,3873.5%
  10. 10Rash2,2813.3%
  11. 11Dizziness2,2613.3%
  12. 12Febrile Neutropenia2,1143.1%
  13. 13Dyspnoea2,0823.0%
  14. 14Vomiting2,0643.0%
  15. 15Asthenia1,9342.8%

Literature

View JSON

Recent PubMed references pinned to Valacyclovir as a MeSH major topic. Citations link to pubmed.ncbi.nlm.nih.gov.

Clinical trials

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The 10 most recently updated of 145 ClinicalTrials.gov registrations naming Valacyclovir as an intervention. Registration is not evidence of efficacy or safety — reference crosswalk only.

Structural analogs

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Ranked by 2D fingerprint (Tanimoto) similarity over PubChem structures. Structural proximity only — not a claim of therapeutic equivalence.

Frequently asked questions

How does Valacyclovir work?
Valacyclovir is an antiviral drug active against α-herpes viruses [see Microbiology (12.4) ].
What is Valacyclovir used for?
According to FDA labeling, Valacyclovir carries indications including: Valacyclovir tablets are a deoxynucleoside analogue DNA polymerase inhibitor indicated for: Adult Patients ( 1.1 ) Cold Sores (Herpes Labialis) Genital Herpes Treatment in immunocompetent patients (initial or recurrent episode) Suppression in immunocompetent or HIV-1–infected patients Reduction of transmission Herpes Zoster Pediatric Patients ( 1.2 ) Cold Sores (Herpes Labialis) Chickenpox Limitations of Use ( 1.3 ) The efficacy and safety of valacyclovir tablets have not been established in immunocompromised patients other than for the suppression of genital herpes in HIV-1–infected patients. 1.1 Adult Patients Cold Sores (Herpes Labialis) Valacyclovir tablets are indicated for treatment of cold sores (herpes labialis).. This is a reference summary of labeled uses, not medical advice or a treatment recommendation.
What class of drug is Valacyclovir?
Valacyclovir is classified as Nucleosides and nucleotides excl. reverse transcriptase inhibitors, Herpes Simplex Virus Nucleoside Analog DNA Polymerase Inhibitor, Herpes Zoster Virus Nucleoside Analog DNA Polymerase Inhibitor, Herpesvirus Nucleoside Analog DNA Polymerase Inhibitor, DNA Polymerase Inhibitors, Decreased DNA Replication.
What are the brand names for Valacyclovir?
Valacyclovir is marketed under brand names including Valtrex.
What are the contraindications for Valacyclovir?
Valacyclovir labeling lists contraindications including: Valacyclovir tablets are contraindicated in patients who have had a demonstrated clinically significant hypersensitivity reaction [e.g., anaphylaxis, severe cutaneous adverse reactions (SCARs)] to valacyclovir, acyclovir, or any component of the formulation [see Warnings and Precautions (5.4) , Adverse Reactions (6.3) ] . Hypersensitivity to valacyclovir (e.g., anaphylaxis), acyclovir, or any component of the formulation.. Always consult the full prescribing information and a clinician.
Note. Data for valacyclovir is illustrative MVP content compiled from public sources. pharmacopeia is for educational and informational use only and is not a substitute for professional medical advice.

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