Molecule of the Week


April 1, 2013

The antiviral drug valaciclovir is used to treat herpes conditions, including shingles. It is marketed under the trade names Valtrex and Zelitrex and has been sold as a generic since 2009.

Valaciclovir is actually a prodrug; after it is taken orally, it is converted by esterase enzymes to the active drug aciclovir, a viral DNA polymerase inhibitor. Valaciclovir’s advantage is that it is more bioavailable than aciclovir.

More about this molecule from CAS, the most authoritative and comprehensive source for chemical information.