Throat paints are viscous liquid preparations containing one or more medicaments and are used for throat and mouth infections. They are highly viscous due to their high content of glycerin. They are made viscous so that the drug would remain in contact with the mucus membrane for a longer time period. Throat paints are applied as such without dilution on the affected area with the help of a brush or cotton plug. They should be stored in colored fluted airtight containers. The general requirements for labeling should be complied with. In addition, the containers should state “For external use only” and “Apply with brush.” Throat paints are useful in the treatment of pharyngitis, laryngitis and follicular tonsillitis. However, they suffer from the drawback of increased salivary secretion due to which the patient may spit out the preparation. The formulation of throat paint requires viscous vehicles, flavoring agents, coloring agents and sweetening agents. Medicaments such as antiseptics, astringents and anti-infectives are commonly incorporated in throat paints.

Example

Mandl’s paint

 

	Iodine	1.25 g
	Potassium iodide	2.5 g
	Purified water	2.5 ml
	Peppermint oil	0.42 ml
	Alcohol (95%)	3.75 ml
	Glycerin (q.s.)	100 ml

 

In this preparation, iodine acts as an antiseptic and potassium iodide dissolves the iodine. Peppermint oil acts as the flavoring agent and produces a cooling effect. Alcohol is used as a solubilizing agent for the peppermint oil. As the preparation contains iodine, it should be prepared in a glass apparatus. Potassium iodide and iodine are dissolved in purified water using a glass mortar and pestle with a small portion of glycerin. To this, peppermint oil dissolved in alcohol is added and mixed and then sufficient glycerin is added to produce the required volume.

Other examples of paints are brilliant green and crystal violet paint, coal tar paint and tannic acid glycerin paint.