Valaciclovir Probenecid

De Bony F, Tod M, Bidault R, et al. Multiple interactions of cimetidine and probenecid with valaciclovir and its metabolite acyclovir. Antimicrob Agents Che-mother 2002 46 458 163. 

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... 

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. ... 

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