February 22, 2024

Excipients: Liquid dosage forms Notes Pharmaceutics, PDF, Books

Excipients: Liquid dosage forms Notes Pharmaceutics, PDF, Books

For the preparation of a liquid dosage form, we need a lot of additives materials. These materials are known as Active Pharmaceutical Ingredients (APIs).


Vehicles are those materials that are chemically inert and don’t have any therapeutic value. But these are used in the formulation of liquid dosage forms to improve the stability, patient acceptability, function of the dosage form.

Examples of aqueous vehicles: Water, glycerin, alcohol, etc.
Examples of oily vehicles: Vegetable oils, mineral oils.


Stabilizers are those materials used to increase the stability of material or formulation by preventing degradation of the product.

According to the material, it varies.


Preservatives are those ingredients used for the preservation or for the protection of the formulation from the attack of microorganisms.

Examples of preservatives: benzoic acid, sorbic acid, sodium benzoate.

Suspending Agents:

Suspending agents are those excipients, which are useful to help active pharmaceutical ingredients to stay suspended into the formulation and prevent the cake formation under the container of the formulation.
Suspending agents are used in the preparation of the suspension.

Emulsifying Agents:

Emulsifying agents are those surface-active ingredients used in the formation of the emulsion. It’s useful to adsorb the water-oil droplet interface.

Examples of emulsifying agents: Gun acacia, Tragacanth.


Solubilizers are those materials used to increase the solubility of a material to improve bioavailability.

Example of solubilizers: Polysorbate.

Coloring agents:

Colouring agents are used in the liquid dosage form to improve the acceptance of consumers.

Examples of natural colours: Titanium dioxide, carotene, ferric oxide, etc.
Examples of Synthetic colours: Erythrosine, Tetrazine, etc.

Flavoring Agents:

Flavouring agents are used to overcome the unpleasant smell of a formulation.
Examples of flavouring agents: Apple, ginger, clove, rose, etc.

Sweetening Agents: 

Sweetening agents are used to overcome the unpleasant taste of the formulation.
Examples of sweetening agents: Sucrose, fructose, saccharin, sorbitol.

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