Valacyclovir is indicated for the following infectious diseases-

• Herpes Zoster Infections (Shingles)
• Genital Herpes
• Chickenpox

Genital Herpes

Herpes

Chicken Pox

Adult Dosing Recommendations

Cold Sores (Herpes Labialis)

• The recommended dosage of VALTREX 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 VALTREX for treatment of initial genital herpes is 1 gram twice daily for 10 days. Therapy was most effective when administered within 48 hours of the onset of signs and symptoms.
• Recurrent Episodes: The recommended dosage of VALTREX for treatment of recurrent genital herpes is 500 mg twice daily for 3 days. Initiate treatment at the first sign or symptom of an episode.
• Suppressive Therapy: The recommended dosage of VALTREX for chronic 66 suppressive therapy of recurrent genital herpes is 1 gram once daily in patients with normal immune function. In patients with a history of 9 or fewer recurrences per year, an alternative dose is 500 mg once daily. 
• In HIV-infected patients with a CD4+ cell count ≥100 cells/mm3, the recommended dosage of VALTREX for chronic suppressive therapy of recurrent genital herpes is 500 mg twice daily. 
• Reduction of Transmission: The recommended dosage of VALTREX for reduction of transmission of genital herpes in patients with a history of 9 or fewer recurrences per year is 500 mg once daily for the source partner. Herpes Zoster: The recommended dosage of VALTREX for treatment of herpes zoster is 1 gram 3 times daily for 7 days. Therapy should be initiated at the earliest sign or symptom of herpes zoster and is most effective when started within 48 hours of the onset of rash. 

Pediatric Dosing Recommendations: 

Cold Sores (Herpes Labialis): The recommended dosage of VALTREX for the treatment of cold sores in pediatric patients ≥12 years of age 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).

Chickenpox: The recommended dosage of VALTREX for treatment of chickenpox in immunocompetent pediatric patients 2 to <18 years of age is 20 mg/kg administered 3 times daily for 5 days. The total dose should not exceed 1 gram 3 times daily. Therapy should be initiated at the earliest sign or symptom 

The most common adverse reactions reported are-

• headache
• nausea
• abdominal pain
• Thrombocytopenic Purpura
• Hemolytic Uremic Syndrome

The only adverse reaction occurring in >10% of pediatric patients of was headache

Headache

Nausea

Abdominal Pain

Purpura

• Thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS) has happened in HIV patients with severe illness, in patients undergoing allogenic bone marrow transplants, and in patients undergoing kidney transplants. If clinical symptoms and laboratory results that are consistent with TTP/HUS appear, stop the treatment.
• 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 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.
• Central nervous system adverse reactions (e.g., agitation, hallucinations, confusion, and encephalopathy): May occur in elderly patients (with or without reduced renal function) and in patients with underlying renal disease who receive higher than recommended doses of Valacyclovir for their level of renal function. Use with caution in elderly patients and reduce dosage in patients with renal impairment