L52: Processing tablets

Question 1

Q: What is an excipient?

Answer 1

A: All the other components of a formulation other than the active drug.

Question 2

Q: What is a medicine?

Answer 2

A: A drug in a form suitable for administration to the public; i.e., a formulation.

Question 3

Q: What is a tablet?

Answer 3

A: A compressed powder consisting of drug and inert excipients.

Question 4

Q: What is a capsule?

Answer 4

A: Drug and excipients contained in a gelatin shell.

Question 5

Q: What is a caplet?

Answer 5

A: A compressed powder in the shape of a capsule.

Question 6

Q: What is the most popular dosage form?

Answer 6

A: Tablets
- no microbial growth
- easier
- cheaper

Question 7

Q: Name some types of tablets

Answer 7

A: Sugar-coated, film-coated, press-coated, controlled release, effervescent, chewable, sublingual , lozenges

Question 8

Q: What is important for tablets like effervescent, soluble, chewable, sublingual, and lozenges?

Answer 8

A: Excipients must be soluble to avoid gritty sensation.

Question 9

Q: List three advantages of tablets.

Answer 9

A: Accurate dosage, convenience, mass production, can alter rate of release

Question 10

Q: What makes tablets difficult for some patients to use?

Answer 10

A: Difficulty swallowing.

Question 11

Q: What formulation issues can tablets face?

Answer 11

A: Poor wetting, low solubility, bitter taste, and moisture sensitivity.

Question 12

Q: What are some essential properties of tablets?

Answer 12

A: Accurate and uniform dose
- uniform in weight, shape
- recognisable
- can be compressed but also able to breakdown in the stomach
- good dissolution rate
- moisture and temp stability

Question 13

Q: What are the three essential properties for particles to be made into tablets?

Answer 13

A: Free-flowing, form strong compacts, and avoid adhesion.

Question 14

Q: Why are excipients often necessary?

Answer 14

A: Few active ingredients have all required properties.

Question 15

Q: What is the sequence of tablet manufacturing steps?

Answer 15

A: Weighing → Dry Mixing(excipients and API for uniformity) → Granulation → Tableting → QC Check → Coating → Dissolution → QA Check.

Question 16

Q: What is the basic principle of tablet machines?

Answer 16

A: Powder is filled, compressed between punches, then ejected.

Question 17

Q: What are the three stages of powder bed compression?

Answer 17

A: Rearrangement when stress is applied, deformation due to stress, bonding of compressed powders.

Question 18

Q: What happens during rearrangement and what influences it?

Answer 18

A: particles rearrange to minimise free space between particles
- this is dictated by the particle size and the frictional forces between the particles

Question 19

Q: What happens during deformation?

Answer 19

A: particles are so closely packed that there are no voids to fill, so a further increase of compression causes the powder to undergo deformation
- can create permanent changes in the shape of the material

Question 20

what are the deformation mechanisms?

Answer 20

elastic deformation, plastic deformation and brittle fragmentation ( we want first 2)

Question 21

Q: what are the materials that undergo plastic deformation?

Answer 21

A: Microcrystalline cellulose, stearic acid, starch, sodium chloride.

Question 22

Q: what are the materials that undergo brittle fragmentation?

Answer 22

A: Sucrose, dibasic calcium phosphate, lactose, calcium carbonate.

Question 23

what occurs during bonding?

Answer 23

• after the application of stress, interparticle bonding occurs which results in the production of a tablet

Question 24

Q: What leads to tablet formation after compression?

Answer 24

A: Inter-particle bonding following sufficient stress and deformation.

Question 25

Q: What are the steps in direct compression?

Answer 25

A: Size reduction(faster dissolution) → Dry mixing(disintigrants, drug, lubricants etc) → Compression.

Question 26

Q: Why must powders be well blended?

Answer 26

A: To ensure drug content uniformity.

Question 27

Q: How is blending reliability improved for dry mixing?

Answer 27

A: By sieving raw materials to remove lumps.

Question 28

Q: Name some common compressible vehicles.

Answer 28

A: - Anhydrous lactose - microcrystalline cellulose - starch dicalcium phosphate

Question 29

Q: What are the typical components in a direct compression tablet?

Answer 29

A: Active drug, diluent, lubricant, disintegrant, glidant, flavours/colours, particulate binder.

Question 30

Q: What is granulation?

Answer 30

A: Adherence of powder particles to form granules.

Question 31

Q: Why are granules preferred over powders?

Answer 31

A: Powder is harder to compress than granules.

Question 32

Q: List three reasons to granulate.

Answer 32

A: Improve flow, increase compressibility, reduce agglomeration.

Question 33

Q: What are the steps in wet granulation?

Answer 33

A: - Grinding down the drugs - blend with excipients - put in mixer - pass through a screen - dry - blend with other excipients - compaction

Question 34

Q: Name three granulating solvents and why there's only a few of them.

Answer 34

A: Water, ethanol(mainly this), isopropanol. - not many options as we cant eliminate all the solvent upon drying

Question 35

Q: What are common polymer binders?

Answer 35

A: Gelatin, starch, PVP.

Question 36

Q: What are key stages in wet granulation-based tablet production?

Answer 36

A: size reduction→dry mixing→ Wet massing →size enlargement→size fractioning→dry mixing →compression - when wet massing and adding material, this increases particle size therefore we need to control size after drying → size fractionation

Question 37

Q: What is an intra-granular excipient?

Answer 37

A: Components like the active drug, filler, binder, and disintegrant (1) mixed before granulation.

Question 38

Q: What is an extra-granular excipient?

Answer 38

A: Components like lubricant, glidant, and disintegrant (2) added after granulation and drying

Question 39

Q: When is dry granulation used?

Answer 39

A: For poor-flowing powders or heat/moisture-sensitive drugs that cant undergo direct compression

Question 40

Q: What is slugging?

Answer 40

A: formulation ingredients are mixed and pre-compressed on a table press which operates at a significantly higher pressure

Question 41

Q: Name three advantages of dry granulation.

Answer 41

A: cheaper, less equipment needed, eliminate addition of moisture and heat