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▪ Suitable for pharmaceutical preparation.
▪ disadvantage of water evaporation and microbial contamination.
▪ e.g. Vanishing cream (morning cream)

Gels

What are gels?
▪ Gels are semisolid systems based on the use of gelling agents (small inorganic particles or
large organic molecule dispersed in liquid vehicle within a 3 dimentional network) to impart
a jellylike matrix
▪ Gels are sometimes called jellies
▪ The advantages of gels are that:
1. They are stable over long periods of time
2. They provide a cooling sensation when applied to the skin
3. They have a good appearance (Translucent, non-greasy)
4. They are suitable vehicles for applying medicaments to skin and mucous
membranes, giving high rates of release of the medicament and rapid absorption.

What are gelling agents?
Substances which when added to an aqueous mixture, increases its viscosity without substantially
modifying its other properties such as taste

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