药物的脂/水溶解度平衡对它们的吸收,分布和排泄有着重要的影响。为使药物分子透过生物膜它们必须有一定的脂溶性。极易溶于水的药物仅是缓慢而无效地透过膜层,随着一系列药物的脂溶性增加,它们的扩散透膜能力增加直达一定的限度值。超过此限度值时,即使更大的脂溶性药物的扩散能力也要降低。表示化合物脂/水溶解度平衡的最常见方法是使用它们的分配系数。 The lipid / water solubility balance of the drug has an important effect on their absorption, distribution, and excretion. In order for the drug molecules to penetrate the biofilm they must have some fat solubility. Very easily soluble in water only slowly and ineffectively through the membrane, with a series of drugs increased fat-soluble, their ability to diffuse through the membrane up to a certain limit. When this value is exceeded, even the larger lipophilic drug has a reduced ability to diffuse. The most common way to express the lipid / water solubility balance of compounds is to use their partition coefficient.