Valtrex tablets 500 mg for virus infections (valaciclovir, valacyclovir, herpes, chickenpox)

General information on Japanese Valtrex tablets 500 mg for virus infections (valaciclovir, herpes, chickenpox)

Package details: 42 tablets

Manufacturer: GlaxoSmithKline K.K., Japan

Active ingredients: valacyclovir hydrochloride (chemical formula C13H21ClN6O4)

Medical effect: Valtrex tablets are effective for the treatment of virus infections, including following:

• herpes simplex,
• herpes zoster,
• chickenpox,
• suppression of onset of herpes simplex virus infection associated with hematopoietic stem cell transplantation,
• suppression of recurrence of genital herpes.

Contraindications and precautions: do not use for pregnant or breastfeeding women. Do not use for patients with renal disorder or on dialysis.

If an allergic reaction occurs, stop using the medicine and consult with your doctor. If you’re taking any other medication or receiving any other treatment, you have to consult with your doctor before use.

Please take a larger amount of water than usual while taking this medicine. However, if you have been instructed to restrict fluid intake, please consult with your doctor in charge.

As this medicine may cause consciousness disorder, pay close attention when driving a car or operating dangerous machinery. Patients with renal dysfunction should avoid operating dangerous machinery or driving a car, as they are more susceptible to consciousness disorder.

Dosage and administration

For herpes simplex: for adults and children with weight of more than 40 kg, take 1 tablet (500 mg of valaciclovir) at a time, 2 times a day.

For suppression of onset of herpes simplex virus infection associated with hematopoietic stem cell transplantation: for adults and children with weight of more than 40 kg, take 1 tablet (500 mg) at a time, 2 times a day from 7 days prior to hematopoietic stem cell transplantation to 35 days after transplantation.

For herpes zoster: for adults and children with weight of more than 40 kg, take 2 tablets (1,000 mg) at a time, 3 times a day.

For chickenpox: for adults and children with weight of more than 40 kg, take 2 tablets (1,000 mg) at a time, 3 times a day.

For suppression of recurrent genital herpes: for adults and children with weight of more than 40 kg, take 1 tablet (500 mg) at a time, once a day. The dosage or frequency of doses may be adjusted according to the symptoms.

In any case, doctor in charge may adjust the dosage according to disease, symptoms, and age of the patient.

How effective are Valtrex tablets 500 mg from Japan for virus infections (valaciclovir, herpes, chickenpox)?

Valtrex tablets contain valacyclovir hydrochloride, the hydrochloride salt of the L-valine ester of acyclovir, a member of the purine (guanine) nucleoside analog drug class. It works by inhibiting viral DNA replication via inhibiting and inactivating viral DNA polymerase, incorporating into the growing viral DNA chain and terminating it. No significant resistance to valaciclovir is found in immunocompetent patients (Yu-Chen Jiang, Hui Feng et al. “New strategies against drug resistance to herpes simplex virus”. International Journal of Oral Science, 2016 Mar; 8(1): 1–6).

Who should use Valtrex tablets 500 mg from Japan?

Valtrex tablets are active against most species in the herpesvirus family. They are effective for the treatment of herpes simplex, herpes zoster and chickenpox, as a suppression of onset of herpes simplex virus infection associated with hematopoietic stem cell transplantation and as a suppression of recurrence of genital herpes. This medicine can be used for both adults and children with weight of more than 40 kg.