A film coating is a thin polymer-based coat applied to solid dosage forms in the pharmaceuticals and complementary medicines industry.
The coating is applied through a spraying process after compression using specialised coating equipment.
The coating can be clear or a vast range of coloured film which can be made in-house or bought as a premix through reputable brands available on the market.
Basic film coating solutions contain water soluble materials that dissolve completely in the gastrointestinal tract and do not modify the drug release characteristics of the dosage form. These are made in aqueous film coating suspensions and contain the following ingredients:
The final quality of the coated product is influenced by the combination of processing parameters during the film coating process. Common coating defects include: rough/orange peel appearance, picking/sticking, peeling, mottling, logo bridging, erosion and colour variation and many of these issues can be addressed by the modification of critical process parameters.
The following are some of the parameters should be considered when establishing the coating process for any particular product:
Refer to Tablet Coating Basics – Part 2 next month for more detail on some of the main critical process parameters.
Vitex Pharmaceuticals Pty Ltd