皮肤对大多数物质形成一道难以渗透的屏障,因此,为了提高局部用药的疗效,就需设法降低这道屏障的功能。采用渗透促进剂或加速剂可取得某些突破。然而,渗透促进剂是否确实促进药物通过角质层,或仅单纯地促进药物从其剂型中释放出来均很难加以确定。例如,渗透促进剂丙二醇,体外实验结果也显示其通过影响药物的热力学活性来提高甾体激素的释放速度。上述两种作用很难单独形成,可能是互为补充的一对。在某些 The skin forms a difficult-to-penetrate barrier to most substances, so to improve the efficacy of a topical regimen, care must be taken to reduce the barrier’s function. Some breakthroughs can be achieved with penetration enhancers or accelerators. However, it is difficult to determine if the permeation enhancer does indeed facilitate the passage of the drug through the stratum corneum, or simply simply promotes the release of the drug from its dosage form. For example, penetration enhancer propylene glycol, in vitro experimental results also show that by affecting the thermodynamic activity of drugs to improve the release rate of steroid hormone. The two roles are difficult to form a separate, may be mutually complementary pair. In some