胰岛素与肝素属于多肽与粘多糖类的高分子,口服给药在消化液中分解,消化道中吸收差,因此不用作口服制剂。然而作为注射剂又有抗原性的问题,所以考虑了这类药物采用直肠吸收的方法。例如加表面活性剂时能促进直肠吸收,但是易于引起直肠粘膜出血等损伤。最近发现水杨酸衍生物(水杨酸钠、3—甲氧基水杨酸钠、5—甲氧基水杨酸钠)对胰岛素 Insulin and heparin belong to the polypeptide and mucopolysaccharide polymers, oral administration decomposition in the digestive juice, poor absorption in the digestive tract, it is not used as an oral preparation. However, as an injectable antigen again, so consider the use of such drugs rectal absorption method. For example, the addition of surfactant can promote rectal absorption, but easily lead to rectal mucosal bleeding and other injuries. Recently, salicylic acid derivatives (sodium salicylate, sodium 3-methoxysalicylate, sodium 5-methoxysalicylate) have been found to inhibit insulin