Solid dosage forms

Question 1

What are some of the disadvantages of tablets?

Answer 1

manufacture requires a series of unit processes - product loss at each stage
drug absorption is dependent on gastric emptying rate
compression difficulties due to powder physical properties

Question 2

What is the definition of excipient?

Answer 2

An inert substance that is used as a diluent or vehicle for preparing a drug product

Question 3

For high dose tablets, the active ingredient is < 5% of the tablet weight. True or false?

Answer 3

False >50% of tablet weight

Question 4

For low dose tablets, what % of tablet weight dose the active ingredient make?

Answer 4

< 5%

Question 5

The total tablet weight should be less than ___mg to be viable to swallow

Answer 5

800mg

Question 6

High dose tablets require a filler. True or false?

Answer 6

False - low dose <5mg tablets do

Question 7

The filler used in tablets should be hygroscopic. True or false?

Answer 7

False - non-hygroscopic as you don’t want it to absorb water as they make bulk of tablet

Question 8

Why is a filler needed in a low dose tablet?

Answer 8

For ease of manufacture and handling

Question 9

What is the need for a disintegrant in a tablet?

Answer 9

To ensure the tablet breaks up into smaller fragments

Question 10

What is the role of a binder in a tablet?

Answer 10

Added to ensure that the tablet can be formed with the required mechanical strength

Question 11

What is the role of a glidant in a tablet?

Answer 11

To improve flowability of the powder - either for direct compaction or for granulation

Question 12

Name a glidant

Answer 12

talc

Question 13

Name a binder

Answer 13

PVP

Question 14

Name a filler

Answer 14

Sucrose

Question 15

Name a disintegrant

Answer 15

Starch

Question 16

What is the role of a lubricant in a tablet?

Answer 16

To ensure that tablet formation and ejection can occur with low friction between the tablet and the die

Question 17

Name a lubricant

Answer 17

Magnesium stearate

Question 18

Why would you want to minimise the amount of lubricant in a tablet, although it helps with tablet formation?

Answer 18

Because they are usually lipophilic and so will hinder the dissolution and disintegration of the tablet if too much is used

Question 19

What is the role of an antiadherent in tablet?

Answer 19

To reduce the adhesion between the powder and the punches which could otherwise lead to uneven tablet surface

Question 20

What is tensile strength used to measure?

Answer 20

adhesive/cohesive properties

Question 21

What is meant by tensile strength?

Answer 21

How easy it is to introduce a breakage in the tablet

Question 22

What does a high angle of repose indicate?

Answer 22

High cohesive forces

Question 23

When the angle of inclination is greater than the frictional force, does the powder slide or stop sliding?

Answer 23

Slide

Question 24

How can powder flow be improved?

Answer 24

Increase the particle size of powder e.g. by granulation
Alter surface forces - controlled temp, humidity etc.
Formulation additives e.g. glidants, lubricants
Change process conditions - vibration assisted hoppers, force feeders

Question 25

What is granulation?

Answer 25

Primary powder particles are made to adhere to form larger multi-particle entities called granules

Question 26

Why use granulation?

Answer 26

Granules flow better than powder Prevent segregation of ingredients Improve compaction Ease of transport as they are less dense than powder and so occupy less vol/unit weight

Question 27

What is the mechanism of granulation? (3 steps)

Answer 27

Nucleation Transition (nuclei growth) Granule growth

Question 28

Wet granulation is suitable for temperature and moisture sensitive material. True or false?

Answer 28

False - dry granulation is

Question 29

What are some advantages of dry granulation?

Answer 29

Economical - less energy costs Low equipment costs Easy to scale up

Question 30

Bulk density affects die filling. True or false?

Answer 30

True

Question 31

Uniformity of content test is recommended for all pharmaceutical preparations. True or false?

Answer 31

False - compulsory

Question 32

How many tablets should be tested for uniformity of content?

Answer 32

More than 5 - to be representative

Question 33

What are the accepted % limit for API in uniformity of content test?

Answer 33

90-110%

Question 34

There is a direct correlation between uniformity of content and tablet weight. True or false?

Answer 34

True

Question 35

In tablet weight testing, no more than two tablets should have a mass difference of more than 20%. True or false?

Answer 35

False - 10%

Question 36

What happens to a tablet that is ingested but doesn't disintegrate in the body?

Answer 36

It gets excreted

Question 37

How many tablets need to fail the disintegration test for it to be repeated on a second full batch?

Answer 37

2 tablets

Question 38

What is the definition of dissolution?

Answer 38

The transfer of molecules or ions from the solid state into solution

Question 39

What are the two methods of conducting dissolution tests?

Answer 39

Stirred vessel method | Continuous flow method

Question 40

Dissolution is independent of temperature. True or false?

Answer 40

False - dependent on temperature

Question 41

If a reaction is exothermic, will dissolution be favoured by an increase in temperature?

Answer 41

No

Question 42

What are the two possible apparatus for dissolution in the stirred vessel method?

Answer 42

Basket | Paddle

Question 43

Which dissolution method is a better mimic of GIT conditions?

Answer 43

Continuous flow

Question 44

The mechanical strength of a tablet it associated with resistance of the solid specimen to what two thing?

Answer 44

Fracturing and attrition

Question 45

What are friability tests used to mimic?

Answer 45

Forces that are present in production, storage and administration

Question 46

In the friability test you are looking for a less than 5% weight loss in the tablet. True or false?

Answer 46

False - less than 1%

Question 47

In a friability test, how many tablets are tested?

Answer 47

20 tablets in revolving cycle

Question 48

When testing the tablets resistance to crushing, if the tablet splits in two, does it pass the test?

Answer 48

Yes

Question 49

What are gastro-retentive tablets designed for?

Answer 49

To be retained in the upper GIT

Question 50

Mucoadhesive tablets are designed to stick for a long period of time. True or false?

Answer 50

True

Question 51

What are the 3 types of coating?

Answer 51

Film Sugar Compression

Question 52

What is titanium dioxide used as in coating?

Answer 52

A colourant

Question 53

Are tablets more evenly coated if a horizontal spray is used or a tilted spray is used?

Answer 53

Tilted

Question 54

What are some problems that are associated with coating?

Answer 54

Erosion, peeling and breakage Poor mechanical strength Uneven coat Tablet peeling

Question 55

Sugar coating involves successive applications of ______ solution

Answer 55

sucrose

Question 56

What are the characteristics of tablets that are coated with a sugar coating?

Answer 56

Immediate release of drug - as sugar is very soluble in water Masked taste of tablet

Question 57

Main reason of using a sugar coating is for masking taste rather than functionality. True or false?

Answer 57

True - would still need a film coat e.g. enteric if you want functionality

Question 58

A sugar coat doesn't add much weight to the total tablet weight. True or false?

Answer 58

False - adds a lot of weight 30-50%

Question 59

Sugar coating a tablet is a quick process. True or false?

Answer 59

False - takes over 8 hours

Question 60

What are the 6 steps involved in sugar coating process?

Answer 60

``` Sealing Subcoating Smoothing Colouring Polishing Printing ```

Question 61

Compression coating allows for 2 drugs to be present in one tablet. True or false?

Answer 61

True - one drug in the coating and one in the core

Question 62

Soft gelatin capsules cannot be filled with liquid. True or false?

Answer 62

False - can be filled with liquid - helps to increase solubility or permeability of drug across cell membrane

Question 63

Soft gel capsules are not suitable for potent drugs. True or false?

Answer 63

False

Question 64

Why is there no risk of leakage in a soft gel capsule?

Answer 64

Because it is one piece that is sealed

Question 65

Why is it harder to have a liquid in a hard capsule?

Answer 65

Because there is risk of leakage - the capsule is made of two pieces

Question 66

Hard capsules are all one size. True or false?

Answer 66

False - they can be different sizes to accommodate for different volumes within the capsule

Question 67

Hard capsules are filled with liquid. True or false?

Answer 67

False - powder, or more normally pellets

Question 68

The hard capsule shell doesn't give any controlled release properties. True or false?

Answer 68

True - if you want controlled release, this has to be done at the granulation stage of the process

Question 69

Hydrolysis only occurs in the presence of water. True or false?

Answer 69

False - water, acid or base

Question 70

Most ibuprofen is supplied as a racemic mixture. Unusually, this drug is converted to the R-form in the body. True or false?

Answer 70

False - converted to the S form

Question 71

What does a maillard reaction occur between?

Answer 71

Lactose and an amide containing drug, resulting in a glycosylamine.

Question 72

How can a maillard reaction be prevented?

Answer 72

By using an alternative diluent to lactose such as mannitol

Question 73

Replacing an aqueous solvent with a non-aqueous solvent will maximise the stability of the drug. Why?

Answer 73

Because it will be less prone to hydrolysis

Question 74

Magnesium stearate only acts as a lubricant. True or false?

Answer 74

False - lubricant, glidant, anit-adherent