Glycerites are solutions or
mixtures of medicinal substances in not less than 50% by weight of glycerin. Most glycerites are viscous while some are of
jelly-like consistency.
Some of the glycerites are
used in their original form as medicinal agent while others are used to prepare
aqueous and alcoholic dilutions of substances which are not readily soluble in
water or alcohol. Glycerin of Phenol, BPC, 1963 is diluted with glycerin to
form the pharmaceutical preparation, Ear Drops with Phenol, BPC 1963. Water
should not be added to this preparation. It reacts with the phenol to produce a
preparation which is caustic and consequently causes damage in the area of
application.
Glycerites are hygroscopic and
therefore, should be stored in tightly closed containers. Glycerin is a
valuable pharmaceutical solvent forming permanent and concentrated solutions
not otherwise obtainable.
EXAMPLES OF GLYCERITES AND THEIR PREPARATION
Starch Glycerites, NF
Other Names: Glyceratum Amyli
and Starch Glycerin
Formula:
Starch 100g
Benzoic Acid 2 g
Purified water 200 ml
Glycerin 700 ml
To make about 1000g
Preparation:
Levigate thoroughly the starch
and benzoic acid with the purified water in a porcelain dish until a smooth mixture
is produced then add the glycerin and mix well. Heat the mixture of a sand bath
to a temperature between 140o – 144o with constant but gentle stirring until a
translucent, jelly-like mass are results. Strain through muslin.
Starch glycerite should be
freshly prepared.
Possible Uses: Emollient, sometimes used as a substitute for fatty
ointment vehicles and as a pill excipient.
Dose: Topically as required.
Tannic Acid Glycerite, NF
Other Names: Glyceritum Acidi Tannici; Glycerite of Tannin; Tannic
Acid Glycerin
Formula:
Tannic Acid 20 g
Exsiccated Sodium Sulfite 0.2
g
Sodium Citrate 1 g
Glycerin, q.s. __________
To make 1000 g
Preparation:
Levigate all the solid ingredients
in a porcelain dish with about half of the glycerin ( ½ of 788 g) until a smooth mixture is produced.
Add the remainder of the glycerin and mix well to make 1000 g. Heat the mixture
on a sand bath to a temperature between 15o and 120o with occasional stirring
until solution is complete.
Uses: Astringent, useful as local application in sore throat and in
mouth sore due to stomatitis. Also it is used to harder nipples to prevent
soreness during nursing as a general astringent.
Remarks: The sodium citrate in formula is added to prevent the
development of an ink-like color in even a minute quantity of iron should be
present.