[Studies on the dissolution and bioavailability of trimethoprim-sulfadiazine-sulfamethoxazole tablets].
A reverse-phase high performance liquid chromatographic method was established for the simultaneous determination of trimethoprim (TMP), sulfadiazine (SD) and sulfamethoxazole (SMZ) in dissolution media. Meanwhile, another reverse-phase high performance liquid chromatographic method was developed for the simultaneous determination of the three drugs mentioned above and their metabolites, N4-acetyl-SD and N4-acetyl-SMZ in serum. The in vitro dissolution and in vivo bioavailability of two commercial trimethoprim-sulfadiazine-sulfamethoxazole tablets (A and B) were studied. Drugs were released far more rapidly from A than from B. Significant difference (P less than 0.001) was observed between the T50 s of the same active principles released from A and B. The in vivo processes of all three active principles in 8 healthy subjects taking two tablets each could be described by one-compartment model with first-order absorption and elimination. Compared with A, the relative bioavailabilities of B were 0.83, 0.73 and 0.78 for TMP, SD and SMZ, respectively. Drugs were absorbed more rapidly from A than from B.
Shao
J
J
Department of Pharmaceutics, China Pharmaceutical University, Nanjing.
Mao
F F
FF
Tu
X D
XD
D000328:Adult; D001682:Biological Availability; D004338:Drug Combinations; D006801:Humans; D008297:Male; D012995:Solubility; D013411:Sulfadiazine / Q000737:chemistry / Q000493:pharmacokinetics*; D013420:Sulfamethoxazole / Q000737:chemistry / Q000493:pharmacokinetics*; D013607:Tablets; D014295:Trimethoprim / Q000737:chemistry / Q000493:pharmacokinetics*
D004338:Drug Combinations; D013607:Tablets; D013411:Sulfadiazine; D014295:Trimethoprim; D013420:Sulfamethoxazole