Generic
Valacyclovir
10 brands available in the market
At a glance
Valacyclovir is an antiviral medicine used in the treatment of herpes labialis, genital herpes infection, and herpes zoster infections. It prevents the multiplication of virus in human cells and clears up the infection.
Description
Valaciclovir is the L-valine ester of aciclovir. A prodrug, it is rapidly converted to aciclovir by intestinal and hepatic metabolism. Aciclovir inhibits DNA synthesis and viral replication and has antiviral activity against herpes simplex virus types 1 (HSV-1) and 2 (HSV-2) and varicella-zoster virus.
Indications
- Herpes labialis
- Genital herpes infection
- Herpes zoster
- Ophthalmic zoster
- Herpes simplex virus infections
- Cytomegalovirus (CMV) infection prophylaxis
Therapeutic class
Herpes simplex & Varicella-zoster virus infections
Pharmacological class
Antiviral
Pharmacology
Valaciclovir is the L-valine ester of aciclovir. A prodrug, it is rapidly converted to aciclovir by intestinal and hepatic metabolism. Aciclovir inhibits DNA synthesis and viral replication.
Mechanism of action
Inhibits viral DNA synthesis, preventing virus multiplication.
Dosage
Adult Dose (Oral):
- Herpes zoster: 1 g three times daily for 7 days
- Genital herpes (initial): 1 g twice daily for 10 days
- Genital herpes (recurrent): 500 mg twice daily for 3-5 days
- Herpes labialis: 2 g twice daily for 1 day
- Herpes simplex suppression: 500 mg once daily
- CMV prophylaxis: 2 g four times daily
Child Dose (>12 years): Same as adult dose
Renal Impairment: Dose adjustment based on creatinine clearance
Administration
- May be taken with or without food
- Swallow whole; do not chew, crush or break
- Take at the same time each day
- Drink plenty of water during treatment
Missed dose
If you miss a dose, take it as soon as possible; if almost time for next dose, skip it; do not double the dose.
Side effects
Common Side Effects:
- Headache
- Nausea
- Abdominal pain
- Diarrhea
- Vomiting
- Dizziness
- Confusion
- Hallucinations
- Rash
- Pruritus
- Renal pain
- Renal impairment
Precautions & warnings
- May decrease alertness; do not drive
- Drink plenty of water during treatment; helps prevent dehydration and kidney damage
- If you have genital herpes, use barrier methods (condoms) and avoid sexual contact while sores are present
- Consult doctor if pregnant or breastfeeding
Contraindications
- Hypersensitivity to valaciclovir, aciclovir, or any excipients
Drug interactions
- Nephrotoxic drugs (aminoglycosides, organoplatinum compounds, iodinated contrast media, methotrexate, pentamidine, foscarnet, ciclosporin, tacrolimus): increased risk of renal failure
- Probenecid and cimetidine: increase peak plasma concentrations and AUC of aciclovir
Food interactions
It is not known whether it is safe to consume alcohol with Valacyclovir; consult your doctor.
Use in pregnancy
Use in Pregnancy: Generally considered safe; animal studies show low or no adverse effects; consult your doctor.
Pregnancy Category: B — always consult a doctor before taking during pregnancy.
Use in lactation
Use in Lactation: Safe; human studies suggest the drug does not pass into breastmilk in significant amount and is not harmful to the baby.
Pediatric use
Chickenpox: 2 years and older: 20 mg/kg three times daily for 5 days; not to exceed 1 g three times daily
Geriatric use
Caution required in elderly; renal function may be reduced
Renal / hepatic impairment
Renal Impairment: Caution needed; dose adjustment based on creatinine clearance
Hepatic Impairment: Safe; no dose adjustment recommended
Overdose effects
Symptoms: Acute renal failure and neurological symptoms (confusion, hallucinations, agitation, decreased consciousness, coma), nausea and vomiting.
Treatment: Observe closely for signs of toxicity; hemodialysis significantly enhances removal of aciclovir.
Storage conditions
Store in a cool & dry place, away from children.