antibioticsbooks

chapter 33 Anti-CMV Agents 213
Ganciclovir dose 5 50 kg 3 5 mg/kg 5 250 mg
ganciclovir
Valganciclovir dose 5 900 mg 3 0.60 bioavailability
5 540 mg of active ganciclovir
This patient would receive more than double
the amount of active ganciclovir if 900 mg
BID of valganciclovir were used. It thus may
be worth considering dose reduction in underweight
patients, particularly if they are at high
risk of toxicity.
• Foscarnet has significant nephrotoxicity. This
can be somewhat attenuated through hydration
with normal saline. Cidofovir is also
nephrotoxic.
• Even if a patient’s isolate of CMV is resistant
to both ganciclovir and foscarnet, it may still be
susceptible to the combination.
What They’re Good For
Ganciclovir and valganciclovir are first-line drugs
for the treatment and prevention of CMV infections.
Valganciclovir is often given to prevent CMV
infection after transplant. Foscarnet is a secondline
agent for CMV that can also be used for severe
or resistant HSV infections. Cidofovir is a secondline
agent for CMV.
Don’t Forget!
Although valganciclovir is oral, it is highly bioavailable
and has adverse effects similar to those
of ganciclovir. Valganciclovir use requires monitoring
for toxicity that is just as rigorous as that for
ganciclovir.