General Description
Synonyms: Argilla; bolus alba; China clay; E559; kaolinite; kaolinum ponderosum; Lion; porcelain clay; Sim 90; weisserton; white bole.
Description: Kaolin occurs as a white to grayish-white colored, unctuous powder free from gritty particles. It has a characteristic earthy or claylike taste, and when moistened with water it becomes darker in color and develops a claylike odor.
Chemical Name: Hydrated aluminum silicate
Functions
Adsorbent; suspending agent; tablet and capsule diluent.
Uses
Kaolin is a naturally occurring mineral used in oral and topical pharmaceutical formulations.
In oral medicines, kaolin has been used as a diluent in tablet and capsule formulations; it has also been used as a suspending vehicle.
In topical preparations, sterilized kaolin has been used in poultices and as a dusting powder.
Therapeutically, kaolin has been used in oral antidiarrheal preparations.
Incompatibilities
The adsorbent properties of kaolin may influence the absorption of other orally administered drugs. Drugs reportedly affected by kaolin include amoxicillin; ampicillin; cimetidine; digoxin; lincomycin; phenytoin; and tetracycline. Warfarin absorption by rat intestine in vitro was reported not to be affected by kaolin. With clindamycin, the rate (but not the amount) of absorption was affected by kaolin.
Safety
Kaolin is used in oral and topical pharmaceutical formulations and is generally regarded as an essentially nontoxic and nonirritant material.
Handling Precautions
Observe normal precautions appropriate to the circumstances and quantity of material handled. The chronic inhalation of kaolin dust can cause diseases of the lung (silicosis or kaolinosis). Eye protection and a dust mask are recommended.
Related Substances
Bentonite; magnesium aluminum silicate.