1941/12/01 by Simon Freed, J.P. Greenhill · 4 citations
Chemistry · #Analytical Methods in Pharmaceuticals
paper · doi:10.1210/jcem-1-12-983
openalex publication_date 1941/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/16
NATURAL ESTROGENS ARE READILY destroyed or inactivated by the liver, so that upon being rapidly absorbed from the site of administra tion their effect lasts only a short time. Retarding the rate of absorption results in an increased period of estrogen action which permits more desirable therapeutic effects. Absorption of estrogens into the blood stream may be delayed a) by chemical combination with fatty acids, b) by dissolving in a medium which one. Nevertheless, there is a certain amount of hesi tation on the part of many physicians to use this method of administering estrogens which requires a special technic. We have therefore, utilised the prin ciple of implantation of crystalline estrogens in a form which does not sacrifice the convenience or practicability of simple injections. This dosage form consists of a suspension of estrone crystals in an aqueous medium. It is postulated that is slowly absorbed, such as oil or wax, and c) by dzpositing the crystalline material directly into the tis sues. With the last method there is a slower uniform rate of absorption over a much longer period of time than with an equal quantity of estrogen in solution since the crystals of estrogen have relatively small surface area and are only slightly soluble in tissue fluids (1).