The
National Formulary (NF) under Gels as a class of Gels in which
structural coherent matrix contains a high portion of liquid, usually
water. They are similar to mucilages because they may be prepared
from gums similar to those used in mucilages but differ from the
latter in having a jelly-like consistency. To obtain a clear
preparation of uniform consistency whole gum of best quality rather
than a powdered gum is desirable. These preparations may be
formulated from acacia, chondrus, gelatin, carboxymethylcellulose and
similar substances in water.
Jellies
are used as lubricant for surgical gloves, catheters and rectal
thermometers. Therapeutic jellies are used for contraceptive
purposes, which contain surface active agents to enhance the
spermatocidal properties of the jelly. Methyl Salicylate and
eucalyptol (aromatics) are often added to give the preparation a
desirable odor. Gels and jellies differ in their physical properties.
Gels are closely related to Magmas.
Examples
of Jellies are Ephedrine Sulfate Jelly NF, Lidocaine Hydrochloride
Jelly USP and Pramoxine Hydrochloride Jelly NF. An example on how to
prepare the Ephedrine Sulfate Jelly NF will be shown.
Ephedrine
Sulfate Jelly NF
Other
Names: Gelatum Ephedrinae Sulfatis; Ephedrine Jelly
Formula:
Ephedrine
Sulfate 10g
Tragacanth
10g
Methyl
Salicylate 0.1ml
Eucalyptol
1ml
Pine
Needle Oil 0.1ml
Glycerin
150g
Purified
water 830ml
To
make about 1000ml
Preparation:
In
the purified water dissolve the ephedrine sulfate, add the glycerin,
tragacanth and the remaining ingredients. Mix well and keep in closed
containers for one week with occasional shaking.
Uses:
Sympathomimetic
Note:
To each 1000g of Ephedrine Sulfate Jelly, 1.6 g of sodium phosphate
may be added as stabilizer.
