Pharmacokinetics and bioavailability of acyclovir sustained-release tablets in dogs.

The pharmacokinetics and bioavailability of acyclovir sustained-release tablets in dogs were investigated. Blood concentrations of acyclovir were determined by RP-HPLC after a single oral dose of two kinds of acyclovir tablets given separately to 6 beagle dogs. The main pharmacokinetics parameters of the acyclovir sustained-release tablet were as follows: T1/2, Tmax and Cmax were 4.10 +/- 0.20 h, 4.05 +/- 0.54 h and 6.90 +/- 0.68 [microg x ml(-1), respectively. MRT was 9.02 +/- 0.44 h. Using acyclovir standard tablet as control, relative bioavailability of the acyclovir sustained-release tablet was 152.2 +/- 49.90%. According to the two-tailed t-test, there was a distinct difference in the data for Tmax, Cmax and AUC between acyclovir sustained-release tablets and acyclovir standard tablets, and the absorbability of acyclovir sustained-release tablets was much better than that of the acyclovir standard tablets.