Kaolin in pharmaceutical preparations: a review

Abstract

Background: Kaolin is a clay mineral with Al2Si2O5(OH)4 structure which can be found in sedimentary rocks also known as clay stones. Kaolin consists of clay materials such as quartz, illite, smectite, and hematite, with the largest constituent component being kaolinite. Kaolin is one of the most common minerals with an abundant presence in the earth's crust compared to other minerals, especially in Indonesia. In the pharmaceutical sector, this clay mineral is widely used in Indonesia. Kaolin is known to be a good adsorbent and has good physical, chemical, and surface physicochemical properties. Objective: This review article aims to provide information about the uses of kaolin in the pharmaceutical industry. Methods: This review article was written by conducting a literature search study method in the PubMed, ScienceDirect, and Google Scholar databases. Results: In the pharmaceutical field, kaolin is used as an excipient in various types of medicinal preparations, one of which is as a suspension agent because of its ability to stabilize suspensions in a deflocculated state as an emulsifying agent, crushing agent, filling agent, and drug carrier. As an active substance, kaolin is widely used because it has a therapeutic activity. In the cosmetic industry, kaolin can be administered in a variety of topical dosage forms which act as skin protective agents or sunscreens. Conclusion: Based on the results of the review, it was found that kaolin, with its abundant presence on earth and its great potential in the pharmaceutical field, is used as an active medicinal substance, excipient ingredient, and in the cosmetic field as a sunscreen. Keywords: Kaolin, excipient, active pharmaceutical ingredient, cosmetics