Aciclovir Probenecid

ACICLOVIR/ VALACICLOVIR ANTIGOUT DRUGS-PROBENECID t levels of acidovir, valacidovir and ganciclovir Competitive inhibition of renal excretion Care with co-administering probenecid with high-dose antivirals... 

The increase in aciclovir AUC with cimetidine is attributable to a reduction in its renal excretion, probably due to competition for secretion by the kidney tubules. When probenecid , (p.775), a renal tubular seeretion eompetitor, and eimetidine were both given the effeets on aeielovir were greater than either drug alone. Cimetidine does not signifieantly alter the pharmaeokineties of fameielovir/penciclovir. ... 

Probenecid reduces the renal excretion and increases the plasma levels of aciclovir, valaciclovir, and ganciclovir. Famciclovir and valganciclovir are predicted to interact similarly. 

Twelve healthy subjeets were given valaciclovir 1 g alone, or with probeneeid 1 g, taken 2 hours earlier. Probenecid increased the AUC0.3 for the prodrug valaeielovir by 22%, and the AUC0.24 for its active metabolite, aciclovir, by 48%. The renal clearance of aciclovir was reduced by 33%, although the total urinary recovery of aciclovir was unchanged. An earlier study had found that oral probenecid 1 g caused a similar increase in the AUC of intravenous aciclovir. ... 

---