Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Medicines design II - solid dosage forms > L7&8 Excipients > Flashcards

L7&8 Excipients Flashcards

0
Q

Why formulate a dose?

A

Patients unlikely to be able to measure accurately. (Especially with low dose)
High doses may be have poor flow/compressibility to make into a tablet.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

Why not administer a pure drug? (6)

A
  • Dose control
  • taste
  • physical properties (partitioning, solubility, BA, stability)
  • to control rate of absorption
  • allow admin via specific route
  • handelling, transportation on and marketing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Taste… Many drugs taste… Can’t be improved by…

A

Very bitter

Film coating

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Panafon actifast claims

A

Paracetamol
Very rapid dissolution therefore rapid adsorption
Less GI problems, suitable for asthmatics
Fast acting pain relief

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Talc is used as

A

A flow agent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Steric acid is used as…

A

A lubricant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Potassium sorb ate is used as

A

A sweetener

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Starch is used as

A

Disintergrants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Triacetic and Hydroxpropymethylcellulose (HPMC) is used as…

A

Film coating

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Sodium bicarbonate is uses as

A

Super disintergrant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Excipients definition

A

All components of the formulation other than the drug

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Excipients require

A

Appropriate evaluation for safety

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Excipients should be

A

Chemically and physiologically inert

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Eg or a moral or religious objection to excipients

A

Genetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Function of excipients (3)

A
  • provide identification
  • enhance BA, solubility and acceptability
  • aid processing of the system during manufacture
  • enhance other attributes of overall safety and effectiveness of drug during storage and use
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Lactose and microcrystalline cellulose are used as…

A

Diluents and compressive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Colloidal sillica used as

A

Flow agent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Magnesium sterate is used as

A

Lubricant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Fumed sillica is used as

A

Adsorbers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What can be adversely affected by excipients?

What is particularly troublesome?

A

Rate of adsorption

Tableting lubricants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Example of excipients inhibiting solubility

A

Magnesium sterate is insoluble and inparts hydrophobicity to formulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

If posible …. To avoid dissolution proplems

A

Minimise percentage of excipient in solid dosage forms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Duleunts or bulking agents are…

A

Added to make tablet a reasonable size

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Principle deluant used is…. Why?

A

Lactose

Pleasant taste, dissolves in water, not hygroscopic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Dicalcium phosphate is used as.... | properties...
Deluant particularly in wet granulation Insoluble in water less hygroscopic Cheap
25
Starches are use.... Property...
``` Deluant Very hygroscopic (>14% moisture uptake) Good disintegration properties ```
26
Micro crystalline cellulose (MCC) is used as... Properties...
Direct compression diluent Excellent compression properties Some disintergrant ion properties
27
Starch is used as .... Properties ...
Diluent Sweet tasting but Very hydroscopic
28
MCC is produced by
Partial hydrolysis of cellulose
29
MCC gives.... Tablet strength from... Compression forces
High tablet strength from low compression forces
30
MCC has good/poor flow
Poor flow as particles a naturally 50micrometers
31
T/f MCC is sensitive to lubricant?
T - lubricant hinders formation of strong bonds between layers (weakens tablet)
32
T/f - MCC is sensitive to moisture?
T-5% uptake
33
Cheaper grades of MCC obtained from
Wood pulp
34
Lower moisture grade MCC has the disadvantage of
Reduced compression
35
High bulk density MCC ...
Aids blending
36
Low bulk density MMC
Increases tablet strength
37
Lubricant function
Prevent adherence of formulation to punches and dies and ensure smooth ejection from these.
38
How do lubricants work?
Form a film of low shear strength between tablet and surface of punch
39
Some lubricants also act as 2
Antiadherance and flow aids
40
2 popular lubricants for punches
Talc and magnesium sterate
41
Popular die lubricant
Steric acid
42
How is magnesium sterate put into things?
Encorporate into dry granules prior to compression | Concentration up to 1%
43
Lubricants in weaponised anthrax?
It's hard to get a small thing into the lung but if you coat it in lubricant it's much easier
44
If you coated a sugar cube in mg sterate and dissovled it you would get a shell. Why?
Very hydrophobic
45
Disadvantages of mg sterate Increased concentration decreases disintegration time, drug dissolution and weakens bond forces (soft tablets) due to hydrophobic nature Incompatibility with many drugs Ethical problems.
Requires additional steps | I
46
Mg sterate incompatible with eg...
Aspirin
47
Ethical problem of mg sterate
Derived from cow fat although plant sources are now available.
48
Gildants are also known as
Flow agents
49
Purpose of flow agent
Added to formulation to improve the flow of granules
50
Flow agents act by
Reducing inter particulate friction
51
Most commonly used and effective flow agent is
Fumed Sillica
52
But what actually is fumed sillica
Amorphous colloidal silicon dioxide
53
What concerntraion of fumes sillica is required
Less than 0.1%
54
Action of flow agents
Reduction of contact area between granules reduces inter particulate cohesion / adhesion and that increases flow ability This is the opposite of geckos sticking to walls
55
Main forces reduced by use of flow agents
Van der waals
56
Sillicified MCC is a combination of
MCC and silicon dioxide During spray drying colloidal sillica is added 10-15nm
57
Advantage of the two in one sillicified MCC
Reduced burden of lubricants Dramatically increases flow Better blending Increases tablet strength
58
Disadvantage of sillicified MCC.?
One supplier, very expensive
59
For effervescent formulations what sort of flow agent do you need?
A soluble one
60
Self lubrication...
I think... Is where it stays in the punch after a number of cycles and then remains consistently lubed
61
People like lubricants as the give
Smooth tablet texture
62
Ideal antifriction agent for decreasing ejection force is
Oil such as Hvo
63
Disintergrants are added to
Promote break up of tablets in vivo
64
Disintergrants are particularly important in 2
Break up of insoluble drugs particularly those of high dose
65
Disintergrants work by
Increasing the surface area of the formed de aggregates by various methods. Thus promoting rapid release of drug.
66
Why do we granulate?
To make sure concentration of drug is consistency throughout tablet,
67
Main Mechanismof disintergrant action
Swelling | Takes in stomach fluid and expands
68
Other mechanisms of disintergrants action
1Porosity and capillary action - draws in fluid which ruptures inter particulate bonds 2Deformation 3Gas production An inter relationship probably occurs in most formulations.
69
Most common disintergrant?
Starch
70
PVP, modified starches and cellulose are used as...
Disintergrants
71
Venalafaxine Xl works by
At certain pH everything inside swells up so drug is pushed out through the tiny whole
72
Super disintergrants - for when starch isn't enough eg
Modified starch -rapid and extensive swelling with minima gelling
73
Modified starch advantage
More effective at lower concentrations. | Reduces problems with compressibility and flows biliary of stach
74
Disadvantaged of modified starch
Hygroscopic
75
Binders are also known as
Adhesives
76
Two methods of adding binders
Slugging (as a powder into the formulation) And As a solution to mixed powders in wet granulation
77
Binding agents function
Bind powders together in wet granulation process or granules during direct compression
78
What must be removed prior to compression
Liquid additives
79
Binder disadvantage
Can effect dissolution rate
80
Typical binding agents 2
starch mucilage and gelatin.
81
Most important binder is... Because...
PVP. Soluble in water and alcohol and releases drug rapidly
82
Typical concentrations of PVP binder
2-10%
83
Function of adsorbants
Hold quantity of fluid in apparently dry state
84
What sort of fluids do we use adsorbants to add
Liquid flavourings, fluid extracts. Oils
85
Commonly used adsorbants
Fumed silica, microcrystalline cellulose, kaolin and magnesium carbonate are commonly employed adsorbents.
86
Why is fumed silica used as adsorbant?
Porus

Medicines design II - solid dosage forms (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions