Valaciclovir
Valaciclovir, also spelled valacyclovir, is an antiviral medication used to treat outbreaks of herpes simplex or herpes zoster (shingles).[2] It is also used to prevent cytomegalovirus following a kidney transplant in high risk cases.[2] It is taken by mouth.[2]
Clinical data
Valtrex, Zelitrex, others
valacyclovir, valacyclovir hydrochloride (USAN US)
- US DailyMed: Valacyclovir
- AU: B3
55%
13–18%
<30 minutes (valaciclovir);
2.5–3.6 hours (aciclovir)
Kidney 40–50% (aciclovir),
faecal 47% (aciclovir)
- 124832-26-4
- as HCl: 124832-27-5
- DB00577
- as HCl: DBSALT000289
- MZ1IW7Q79D
- as HCl: G447S0T1VC
- CHEBI:35854
- as HCl: CHEBI:9919
- ChEMBL1349
- as HCl: ChEMBL1201110
C13H20N6O4
324.341 g·mol−1
Common side effects include headache and vomiting.[2] Severe side effects may include kidney problems.[2] Use in pregnancy appears to be safe.[2] It is a prodrug, which works after being converted to aciclovir in a person's body.[2]
Valaciclovir was patented in 1987 and came into medical use in 1995.[3][4] It is on the World Health Organization's List of Essential Medicines.[5] It is available as a generic medication.[6] In 2021, it was the 114th most commonly prescribed medication in the United States, with more than 5 million prescriptions.[7][8]
Valaciclovir is used for the treatment of HSV and VZV infections, including:[9]
It has shown promise as a treatment for infectious mononucleosis[12][13][14] and is preventively administered in suspected cases of herpes B virus exposure.[15]
Bell's palsy does not seem to benefit from using valaciclovir as its only treatment.[16][17]
Adverse effects[edit]
Common adverse drug reactions (≥1% of people) associated with valaciclovir are the same as for aciclovir, its active metabolite. They include: nausea, vomiting, diarrhea and headache. Infrequent adverse effects (0.1–1% of patients) include: agitation, vertigo, confusion, dizziness, edema, arthralgia, sore throat, constipation, abdominal pain, rash, weakness and/or renal impairment. Rare adverse effects (<0.1% of patients) include: coma, seizures, neutropenia, leukopenia, tremor, ataxia, encephalopathy, psychotic symptoms, crystalluria, anorexia, fatigue, hepatitis, Stevens–Johnson syndrome, toxic epidermal necrolysis and/or anaphylaxis.[9]
Society and culture[edit]
Brand names[edit]
It is marketed by GlaxoSmithKline under the brand names Valtrex[1] and Zelitrex. Valaciclovir has been available as a generic drug in the U.S. since November 2009.[25]