VALACYCLOVIR
(Valtrex)Standard Prescription
Valacyclovir __ mg PO ___ {frequency} x __ days
Dosages
Varicella zoster (Chickenpox) in Immunocompetent
2 to <18 yrs: 20 mg/kg/dose PO TID x 5 days.
Maximum: 1 g/dose
Herpes zoster (Shingles)
Adolescents/Adults: 1 g PO TID x 7 days
Mucocutaneous HSV Infection
(from PK studies only, no clinical efficacy data)
3 mo to 12 yo: 10-20 mg/kg/dose PO BID to TID
HSV or VZV Prophylaxis in Transplant Patients
<40 kg: 250 mg PO BID
>40 kg: 500 mg PO BID
Genital HSV Infection in Adolescents or Adults
Treatment: 1 g PO BID x 7-10 days
Suppressive therapy: 500-1000 mg PO once daily
Episodic therapy: 500 mg PO BID x 3 days
Recurrent herpes labialis
>=12 yrs: 2000 mg PO BID x 1 day
2 to <18 yrs: 20 mg/kg/dose PO TID x 5 days.
Maximum: 1 g/dose
Herpes zoster (Shingles)
Adolescents/Adults: 1 g PO TID x 7 days
Mucocutaneous HSV Infection
(from PK studies only, no clinical efficacy data)
3 mo to 12 yo: 10-20 mg/kg/dose PO BID to TID
HSV or VZV Prophylaxis in Transplant Patients
<40 kg: 250 mg PO BID
>40 kg: 500 mg PO BID
Genital HSV Infection in Adolescents or Adults
Treatment: 1 g PO BID x 7-10 days
Suppressive therapy: 500-1000 mg PO once daily
Episodic therapy: 500 mg PO BID x 3 days
Recurrent herpes labialis
>=12 yrs: 2000 mg PO BID x 1 day
Mechanism of Action
Antiviral agent. Prodrug of acyclovir that is rapidly converted to acyclovir after oral administration.
Forms Supplied
tablet: 500 mg
suspension (BCCH): 50 mg/mL
suspension (BCCH): 50 mg/mL
Comments
Prodrug of acyclovir that is rapidly converted to acyclovir after oral administration.
Bioavailability of 43-64%, compared to oral acyclovir bioavailability of 15-30%.
For Varicella zoster (chicken pox) in immunocompetent patients, treatment must be started within 24 hr of rash for clinical benefit.
Oral valacyclovir efficacy and safety has not been established in infants younger than two years of age, and overall clinical experience is limited in children. If the infection is considered potentially life threatening, IV acyclovir is the treatment of choice.
Dosage adjustment is required in renal impairment.
May cause nausea, vomiting, diarrhea, headache, dizziness, neurotoxicity, arthralgia, fatigue, rash, insomnia, fever.
Bioavailability of 43-64%, compared to oral acyclovir bioavailability of 15-30%.
For Varicella zoster (chicken pox) in immunocompetent patients, treatment must be started within 24 hr of rash for clinical benefit.
Oral valacyclovir efficacy and safety has not been established in infants younger than two years of age, and overall clinical experience is limited in children. If the infection is considered potentially life threatening, IV acyclovir is the treatment of choice.
Dosage adjustment is required in renal impairment.
May cause nausea, vomiting, diarrhea, headache, dizziness, neurotoxicity, arthralgia, fatigue, rash, insomnia, fever.
References
6, 44, 358, 359, 360, 631
Last Edited
2022-09-13 06:15:25