Tablets

Question 1

What is a tablet?

Answer 1

A solid preperation manufactured by compressing uniform volumes of particles which contain a single dose of 1 or more APIs and excipeints

Question 2

Advantages of tablets

Answer 2

Good patient compliance
Convenient to handle, take and store
Accurate dosing
Cheap and robust

Question 3

Disadvantages of tablets

Answer 3

Generally systemic delivery
Poor bioavailability
Must be swallowed
First pass metabolism/GI tract instability
Local irritation
Extensive developmental work

Question 4

What does disintegration rate of oral tablets depend on?

Answer 4

Formulation and production factors

Question 5

What is absorportion rate of oral tablets dependent on?

Answer 5

Lipophilicty

Question 6

Why do chewable tablets not require disintegrants?

Answer 6

Mechanical disintegration occurs in the mouth

Question 7

What is a disadvantage of chewable tablets?

Answer 7

Flavourings and colourings are commonly used which can cause reactions

Question 8

How do effervescent tablets work?

Answer 8

Tablet is dissolved in water as a reaction between bicarbonate and an acid such as citric acid to release CO2 and facilitate disintegration and dissolution

Question 9

How do compressed lozenges work?

Answer 9

Dissolves in saliva and into stomach with swallowing so must be water soluble

Question 10

Where are sublingual tablets taken?

Answer 10

Under the tongue

Question 11

Where are buccal tablets taken?

Answer 11

Side of the cheek or between upper lip and gum

Question 12

What are advantages to buccal and sublingual drug delivery?

Answer 12

Rapid systemic delivery that avoids first pass metabolism due to absorption in highly vascularised areas of the mouth

Question 13

What is an ideal powder blend?

Answer 13

Homogeneous
Free flowing
Coheres and adheres
Does not adhere to tooling

Question 14

What is the role of diluent in tablets?

Answer 14

Increases tablet’s bulk density and size
Achieves required strength

Question 15

Examples of diluents

Answer 15

Lactulose and Microcrystalline cellulose

Question 16

What is the role of disintegrants in tablets?

Answer 16

Promotes rapid tablet disintegration
Important to overcome binders

Question 17

Examples of disintegrants

Answer 17

Ac-Di-Sol and starch

Question 18

What is the role of binder in tablets?

Answer 18

Improve mechanical strength by binding particles
Helps to agglomerate

Question 19

How are binders classified?

Answer 19

By grade, type and molecular weight

Question 20

Examples of binders in tablets

Answer 20

PVP, gelatine and sucrose

Question 21

What is the role of glidants in tablets?

Answer 21

Improve powder flow by reducing inter-particulate friction
Tiny particles coat other particles to allow them to free flow against each other

Question 22

What is the role of lubricant in tablets?

Answer 22

Reduce friction between the tablet and machine during manufacture

Question 23

Examples of glidants

Answer 23

Magnesium stearate

Question 24

Advantages of direct compression

Answer 24

Reduction in manufacturing time and costs
Faster drug dissolution

Question 25

Disadvantages of direct compression

Answer 25

Specialist fillers and binders needed Powder must have good flow properties Poor drug compatibility can occur Poor colour uniformity can occur

Question 26

What is granulation?

Answer 26

Primary power particles adhere to form granules

Question 27

Advantages of granulation

Answer 27

Improves homogeneity and prevents powder segregation Increases bulk density Improves powder flow properties

Question 28

Disadvantages of granulation

Answer 28

Increase in production time and cost due to more unit processes May cause drug hydrolysis

Question 29

What is powder compression?

Answer 29

Forces particles into close proximity to each other by confined compression Particles cohere into a porous solid specimen of defined geometry as a result of 3 stages

Question 30

What are the 3 stages of powder compression?

Answer 30

Die filling, tablet formulation and tablet ejection

Question 31

How does a single-punch tablet press work?

Answer 31

One set of tooling Hopper filled with powder, moves back and forth to fill the die ' Upper punch descends to compress powder Lower punch ejects tablet Output of 200 tablets per minute

Question 32

When are single tablet presses used?

Answer 32

In clinical trials to produce small batches

Question 33

How does a rotary tablet press work?

Answer 33

Multiple sets of tooling Powder flows by gravity from hopper to die table and fed into die by powder feeder Punches compress tablet and feeder knocks tablets to eject Can output thousands of tablets per minute in mass production

Question 34

What is picking?

Answer 34

A specific type of sticking in which particles stick within the lettering or logos of punches

Question 35

What is lamination?

Answer 35

Separation of tablets into distinct horizontal layers in any part of the tablet other than the top

Question 36

What is capping?

Answer 36

Top of tablet fractures and/or breaks free from the rest of the tablet

Question 37

What is chipping?

Answer 37

Breaking of tablet edge

Question 38

What are reasons for coating tablets?

Answer 38

Protect the drug Mask the taste Ease of handling Modified release characteristics Rapid identification Ease of swallowing

Question 39

What is film coating?

Answer 39

Sprayed onto rotating tablets to increase water solubility Can be polymers, plasticizers and colourants

Question 40

What is sugar coating?

Answer 40

A sucrose based syrup and increases water solubility

Question 41

What are the 6 steps of sugar coating?

Answer 41

Sealing, subcoating, smoothing, colouring, polishing and printing

Question 42

What is compression coating?

Answer 42

Compaction of granular particles around tablet core in a tablet machine Less common due to complex process

Question 43

What are tablet attributes?

Answer 43

Contain correct dose Consistent weight, size and appearance Have sufficient mechanical strength Formulated for patient acceptance

Question 44

Why are tablets tested?

Answer 44

To ensure patients receive a tablet which contains required amount of API Ensures tablets possess a suitable mechanical strength to avoid crumbling or breaking To ensure tablet releases its active ingredients over a specific period To ensure microbiological quality of tablets

Question 45

Why is a friability test undertaken?

Answer 45

To mimic the forces encountered during handling

Question 46

What is dissolution?

Answer 46

Measure of cumulative drug release as a function of time