Valacyclovir - Dosage, Side Effects and Use in Shingles Treatment

Valacyclovir or Valaciclovir is an antiviral drug used in the treatment and management of herpes simplex and herpes zoster (shingles). It is a prodrug, being converted in vivo to aciclovir and is marketed under the trade name Valtrex or Zelitrex.
Valacyclovir is currently also being marketed in generic form in the United States and other countries.

Valacyclovir - Mechanism of action

Aciclovir, the active metabolite of valaciclovir, is active against most species in the herpesvirus family. In descending order of activity:
* Herpes simplex virus type I (HSV-1)
* Herpes simplex virus type II (HSV-2)
* Varicella zoster virus (VZV)
* Epstein-Barr virus (EBV)
* Cytomegalovirus (CMV)
Activity is predominantly active against HSV, and to a lesser extent VZV. It is only of limited efficacy against EBV and CMV, however, valacyclovir has recently been shown to lower or eliminate the presence of the Epstein-Barr virus in subjects afflicted with acute mononucleosis, leading to a significant decrease in the severity of symptoms. It is inactive against latent viruses in nerve ganglia.

Valacyclovir - Clinical use

Valacyclovir is indicated for the treatment of HSV and VZV infections, including:
* Genital herpes simplex (treatment and prophylaxis)
* Reduction of HSV transmission from people with recurrent infection to uninfected individuals
* Herpes zoster (shingles)
* Prevention of CMV disease following organ transplantation
It has shown promise as a treatment for infectious mononucleosis and is preventatively administered in suspected cases of Herpes B Virus exposure.

Availability And Packaging

Valacyclovir is available in the form of Generic Valtrex Capsules in 500mg and 1 gram tablets, the active ingredient being valacyclovir hydrochloride, with the inactive ingredients carnauba wax, crospovidone, microcrystalline cellulose, colloidal silicon dioxide, FD&C Blue No. 2 Lake, hypromellose, magnesium stearate, polyethylene glycol, polysorbate 80, povidone, and titanium dioxide.

Additional Information On Valacyclovir

For further information refer to the manufacturers pamphlet on Valtrex: GlaxoSmithKline - Valtrex Prescribing Information

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