国外关于相同标示量四环素片在体内吸收方面发现显著生物利用度差异的报道较多。国内也有经尿药浓度的测定证明国产四环素片存在着显著生物利用度差异的报道。现英国药典(1980年版)已收载有四环素片的释放度标准,作为医药工业优级品考核项目。美国药学会将可能产生生物有效度差异的品种分为高、中、低三类,四环素属于中间这一类。由于四环素在消化道吸收 Foreign reports on the same marked amount of tetracycline tablets found significant differences in bioavailability in the body absorption. There are also the determination of the concentration of urine by the domestic domestic tetracycline evidence of significant differences in bioavailability reported. Now the United Kingdom Pharmacopoeia (1980 edition) has contained the release of tetracycline standards, as the pharmaceutical industry superior items test items. The American Pharmaceutical Association classifies breeds that may have differences in the bioavailability into three categories: high, medium, and low, and tetracycline belongs to the middle class. Because tetracycline is absorbed in the digestive tract