Film Coating VS Sugar Coating

a) Film Coating

Film coating is defined as the process that involves the application of a thin and uniform layer of polymer formulation on the surface of different types of medication such as capsules, powders, pills, etc.

This coating is applied for aesthetic purposes and to prevent deterioration of inner drugs due to environmental elements.

b) Sugar Coating

Sugarcoating is the process in which a thick and hard sugar coat is spread over the surface of tablets.  It is mostly done for purpose to improving the bitter harsh odor and taste of tablets.

It is a traditional technique of pharmaceutical coating and has been in use since the 19^th century.

i.Appearance

a)Film Coating

• Film coating maintains the original shape and form of the tablets. These coatings are not glossy as compared to sugar coating.
• The thickness of the film coating is about 20-100 µm.
• Logos and break-lines are easily visible on the surface of tablets.

b)Sugar Coating

• Sugar-coated pills are rounded and smooth in form having uniform color and shiny. These tablets are polished and glossy in their appearance.
• The coating thickness is about 0.5 mm to 20 mm.
• It is not possible to see logos and crack-lines on the surface of sugar-coated tablets.

II.Advantages

• a)Film Coating
  
• Weight

There is minimal weight increase during the process of film coating approximately about 1-2%.

• Formulation Flexibility

Film coating has huge formulation flexibility as it employs a wide variety of materials and coating systems.

• Variety of Oral Dosage Forms

Film coating is applied to a wide variety of medications like tablets, capsules, granules, pellets, powders.

• Visual Marking

Logos and company marks can be visually discerned with a film coating.

• Diabetic Patients

Film-coated tablets and capsules are appropriate for diabetic patients.

• b)Sugar Coating
  

• Swallowability

Sugarcoating helps in swallowing large tablets.

• Flammable Materials

The materials used in sugar-coating are non-flammable and do not pose the risk of explosion.

III.Disadvantages

a)Film Coating

• Flammable Ingredients

The organic solvent employed as vehicles during film coating is quite flammable and can cause an explosion. Such as ethanol, methanol, methylene chloride.

• Toxic Substances

The solvent used in film coating are toxic and pose a serious health hazard to operating personnel.

b) Sugar Coating

• Weight

There is a considerable increase in the weight of the tablets about 30-50% after the application of sugar coat.

• Embossing

It is difficult to emboss sugar-coated tablets, so identification is printed on the tablets.

• Diabetic Patients

Diabetic patients cannot take sugar-coated tablets as these tablets increase blood sugar levels.

Ⅳ.Ingredients

a)Film Coating

Different materials used in film coating are

• Film Former/ Polymers

These materials are the main component of film coating and impact the characteristics of the film. These materials improve the aesthetic characteristics of tablets and provide resistance to medications against light, oxygen, and heat.

Some polymers are Hydroxy Propyl Methyl Cellulose (HPMC), Polyethylene glycol, Acrylate polymers.

• Solvents

These substances are used to dissolve the polymers. These solvents aid in the spread of film on the exterior of tablets. Some solvents used in film coating are water, acetone, ketone, and alcohol.

• Plasticizer

Plasticizers such as glycerol, coconut oil are employed to alter the characteristics of the polymer. These substances enhance the film adhesion and viscosity of film formers

• Opacifier

These opacifiers like titanium oxide, talc, magnesium oxide is applied to mask the main color and to provide light protection.

b) Sugar Coating

Materials used in sugar-coating are

• Sugar

As the name indicates sugar such as sucrose, sorbitol, and glucose are the main components of sugar coating.  The concentration of sugar syrup in the coating is about 50-60%.

• Fillers

These materials maintain the form of a coat and increase its mass. Examples of filler are talc, corn starch.

• Binders

These materials improve the strength and elasticity of the sugar coating. These include polyvinyl acetate, starch, and agar.

• Smoothing Agents

These materials like syrup and acacia gum act as the lubricant and smooth the coat exterior.

• Polishing Agents

Polishing agents such as carnauba wax and beeswax increase the intensity and reflectivity of the coloring dye.