Exam 1 Tablet Coating Flashcards
Purposes of tablet coating
Protect from environment and increase stability
Mask unpleasant taste/odor
Easier swallowing
Improve product identity
Minimize cross contamination from powder dust
Improve appearance
Reduce abrasion and attrition
Modify drug release (i.e. Enteric coated)
Primary sugar used in sugar coating
Sucrose
Disadvantages of sugar coating
Skilled manpower
Protracted and tedious
Six main steps in sugar coating:
A. Smoothing, subcoating, color coating, sealing, polishing, printing
B. Sealing, subcoating, smoothing, color coating, polishing, printing
C. Sealing, smoothing, subcoating, color coating, printing, polishing
B: sealing, subcoating, smoothing, color coating, polishing, printing
Protects the core from water, and uses alcoholic solutions of resins such as shellac, zein, and cellulose acetate phthalate. May require more than one application
Sealing
True or False: Sugar coating often results in a 50-100% increase in weight, that occurs mainly at the subcoating step
True
________ is when a sticky coating of gelatin, acacia, and sucrose is applied to sealed tablets, followed by a dusting powder application which reduces stickiness and allows tablet buildup
Subcoating
The subcoat is formed from alternate layers of ______ ingredients and ______ components
Solution ingredients and powdered components
The tablet must be ________ out before color coating is applied, where a solution containing 60-70% sugar solids and 1-5% titanium dioxide is applied
Smoothed out
In the smoothing out process, titanium dioxide acts as a(n) ________.
Opacifier
Most critical step in the coating process, that involves multiple applications of materials that are either water-soluble dyes or water-insoluble inorganic pigments and lakes
Color coating
Water soluble dye is dissolved in ______ and applied in (small / large) quantities
Dissolved in syrup; applied in small quantities
Up to how many individual color applications may be necessary for water-soluble dyes?
60
Pigments (opaque) are _______ in syrup
Pigments are dispersed in syrup
What results from combining pigments/lakes with an opacifier such as titanium dioxide?
Color develops rapidly and dries faster with a thinner coat that results in a shorter processing time
Process used to enhance elegance with the use of a mixture of waxes (water-insoluble) and a cloth lined pan
Polishing
Spheres made of sugar and starch that mean “without equal” in French
Nonpareils
How is a film coat applied?
Continuously by spraying coating liquid onto a moving mass of product
Advantages of film coating
Minimal weight increase (2-3%) Shorter processing time Increased efficiency and output Increase in flexibility and formulations Improved resistance to chipping
What type of coating liquids are used currently?
Water-based
Materials used in film coating
Polymer, plasticizer, colorant, and vehicle
What is the purpose of a plasticizer in a film coat?
Makes the film flexible
Inactive ingredients in film coat
Crospovidone, HPMC, polethylene glycol, povidone, titanium dioxide
True or False: Polymers on film coats must dissolve in GI fluid to allow release of drug
True
_______ ______, such as HPMC and methylcellulose, are preferred in film coating
Cellulose ethers
Glycerin, propylene glycol, citrate esters and phthalate esters are ________ which improves flexibility of the film and adhesion to the substrate
Plasticizers
Coating that remains intact in stomach, but dissolves and contents are released in intestine
Delayed release
Variation of coating that releases some drug into the stomach, and remainder is later released in the intestine
Repeat-action effect
True or False: Most enteric coatings are weak bases
False: weak acids
Enteric coats are (dissociated / undissociated) in the stomach
Undissociated
_________ polymers are commonly used in enteric coating
Pthalate
These coating control the release of the drug so that it is made available to the body over a prolonged period of time
Sustained release coating
What are common materials used for sustained release coating?
- Mixtures of waxes and fatty acids
- Zein
- Shellac
Synthetic polymers that are commercially available as aqueous dispersions
Latexes
