Flavoring and coloring agents are added to increase patient acceptance.

The choice of color should be associated with flavor used to improve the attractiveness by the patient. Only sweetening agent are not capable of complete taste masking of unpleasant drugs therefore, a flavoring agents are incorporated. Color aids in identification of the product. The color used should be acceptable by the particular country.

Flavoring Agent in Pharmaceutical Suspensions

The four basic taste sensations are salty, sweet, bitter and sour. It has been proposed that certain flavours should be used to mask these specific taste sensations. In particular:

Most widely used Flavoring agents are as follows:

AcaciaFennel OilPeppermint
Anise OilGingerRaspberry
Caraway OilGlycerinRose Oil
CardamonGlycerrhizaRosemary Oil
Cherry syrupHoneySarsaparilla syrup
CinnamonLavender OilSpearmint Oil
Citric acid syrupLemon OilThyme Oil
Clove OilMannitolVanilla
CocoaNutmeg OilTolu balsam syrup
Coriander OilOrange OilWild cherry syrup
Ethyl vanillinOrange flower water

Usually a combination of flavours is used to achieve the optimal taste-masking property.

Coloring Agents in Pharmaceutical Suspensions

Colours are pharmaceutical ingredients that impart the preferred colour to the formulation. When used in combination with flavours, the selected colour should ‘match’ the flavour of the formulation, e.g. green with mint-flavoured, red for strawberry-flavoured formulations.
Colors are obtained from natural or synthetic sources. Natural colors are obtained from mineral, plant and animal sources. Mineral colors (also called as pigments) are used to color lotions, cosmetics, and other external preparations. Plant colors are most widely used for oral suspension. The synthetic dyes should be used within range of 0.0005 % to 0.001 % depending upon the depth of color required and thickness of column of the container to be viewed in it.

Most widely used colors are as follows.
1. White:
  • Titanium dioxide
2. Blue
  • Brilliant blue
  • Indigo carmine
  • Indigo
3. Red
  • Amaranth
  • Carmine
4. Yellow
  • Tartarazine
  • Sunset yellow
  • Carrots
  • Saffron
  • Annatto seeds(yellow to orange)
  • Madder plant(reddish yellow)
5. Green
  • Chlorophyll

6. Brown
  • Caramel (brown)