PROTECTIVE AND ABSORBENTS – Pharmaceutical Inorganic Chemistry B. Pharma 1st Semester


This group of GIT agents is commonly used for the treatment
of mild diarrhea and dysentery or other disturbances of GIT tract because of
their ability to adsorb gases, toxins and bacteria.

Diarrhea is a symptom but not a disease. It mainly occurs
because of improper digestion or absorption of food or by bacterial infection.
Diarrhea may be acute or chronic. Diarrhea is a serious condition, particularly
for very young or elderly patients, because there will be loss of fluids and
electrolytes can lead to dehydration and electrolyte imbalances.

Many chemical agents are used to treat diarrhea. Their main
action is of protective and adsorbent in nature. Chemically they are inert and
insoluble salts and they form a protective layer or coat on the mucosal
membrane and provide a mechanical protection.

Furthermore, they adsorb the toxin, which are able to
stimulate flow of electrolytes into intestine causing watery stool. They may or
may not have antibacterial action, in case of serious cases they are advised to
take antibacterial or antispasmodic drugs. The inorganic compounds used as
protective and adsorbent are bismuth salts, special clays like light kaolin and
activated charcoal.

Properties of protective and

    Chemically inert

    Used in treatment
of mild diarrhoea and dysentery

    Ability to absorb
gases, toxins and bacteria

    Form a protective
layer on painful ulcers in GIT

Light Kaolin

Synonym: Hydrated
aluminum silicate.

Chemical formula:

Method of Preparation:
It is prepared from natural clay

It involves the
following steps:

• Powdering

• Particles separation by means of electrical sedimentation

• Purification from gritty particles and other impurities by

• Drying

• Storing in suitable container

How does it work?

Kaolin acts as a protective coating for the mouth to
decrease pain associated with radiation- induced damage.

Storage: Store
protected from moisture.

Medicinal uses:

dysentery, colitis and cholera

    Adsorbent in food
and alkaloidal poisoning


    Dusting Powders
and filter aids


Chemical Formula:


Description: Pale
buff or yellowish brown odorless, with slight earthy taste, Occurs as fine
powder practically insoluble in water and all inorganic solvents.

Medicinal uses:
Used as suspending, emulsifying and stabilizing agent, excellent emulsifier for
o/w emulsions Used as a base for pharmaceutical preparations such as ointments,
plasters etc. It is also used as an adsorbent

Storage: It
should be stored in airtight container in a cool and dry place.

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