D3 and D4: Medicine design and manufacturing- powder-based medicines

Question 1

what are the different types of powder-based medicines?

Answer 1

-bulk and wrapped powders
-capsules
-tablets

Question 2

Describe powder medicines

Answer 2

-powders can be medicines themselves
-drug powder mixed with powder excipients
-packed as ‘single-dose’ or in ‘multi dose’ containers

Question 3

Describe bulk powders

Answer 3

Several doses packed in a container suitable for the route of administration

Question 4

advantages of oral bulk and wrapped powders?

Answer 4

-patients who struggle swallowing tablets or capsules
-more stable than liquids (less chemical degradation and very low risk of microbial growth)
-good way to give large doses of drug by mouth
-fast dissolution so fast action

Question 5

Describe the issue with moisture with powders

Answer 5

-absorbs water (hygroscopic)
-can dissolve during processing and storage (deliquescent)
-can stick together (caking)
-Therefore must always be protected from moisture e.g using suitable packaging and store in dry conditions

Question 6

Describe the issues with flow with powders?

Answer 6

-poor flow causes inaccurate/ inconsistent packaging
-Size, shape, moisture, surface charge affect ‘flowability’ → must be controlled

Question 7

Describe the issue with mixing and separation with powders

Answer 7

-poor mixing can lead to inaccurate dosing
-powder mixes can unmix during movement (transport, pouring, mixing)

Question 8

Describe oral bulk powders

Answer 8

-packed in jar or vial (spoonfuls of powder put in food or drink, easy to take)
-Reconstituted in water before dispensing (ex: antibiotics for children) – useful when drug is unstable in water

Question 9

how do you solve mixing and separation issues with powders?

Answer 9

-equalise particle sizes (grinding and sieving)
-mix equal amounts of powders (geometric mixing)
-granulation; powders are bound together to form larger particles, usually spherical (‘granules’)

Question 10

what is dry granulation

Answer 10

dry powders compressed by metal rollers

Question 11

what is wet granulation

Answer 11

powder mixture is wetted with a solution of polymer (binder)

Question 12

how do granules improve mixing and separation of powders?

Answer 12

Powders can not separate
Flow better due to large size
(sieve and dry)

Question 13

Describe wrapped powders and sachets

Answer 13

-One single dose of powder mixture packed in a sealed small bag made of paper, foil or plastic.
-More accurate dosing and more convenient
-Better protection against moisture

Question 14

what are the different excipients in bulk and wrapped powders?

Answer 14

Bulking agents (fillers/diluents), granulating agents (Binders), effervescent mixtures, flow aid (glidants), anti-caking agents, surfactants, flavours, colours

Question 15

many polymers are used as…

Answer 15

excipients (can be natural of synthetic polymers)

Question 16

Describe capsules

Answer 16

-Small ‘edible packages’ filled with one single dose unit
-hard polymer shell soluble in water (gelatin or HPMC)
-Filled with powder mixture, granules, small tablets or combination

Question 17

why do we used hard capsules?

Answer 17

-easy to swallow
-different sizes available
-shell adds protection
-shell can be coloured (identification) or coated (delay release)
-some can be opened
-easier to manufacture than tablets

Question 18

Describe soft capsules

Answer 18

-not as common
-shell made of gelatin, water and platicizer polymer
-used for oils, liquids, semi solids
-larger but easier to swallow

Question 19

Function of bulking agent (fillers/dilutents) excipient?

Answer 19

add bulk as the drug may only be a few mg

Question 20

Function of granulating agents (binders) excipient?

Answer 20

bind powders into granules

Question 21

Function of effervescent mixtures excipient?

Answer 21

produce CO2, faster dissolution

Question 22

Function of flow aid (glidants) excipients?

Answer 22

improve flow of powders

Question 23

Function of anti-caking agents excipients?

Answer 23

adsorb water

Question 24

Function of surfactants excipients?

Answer 24

Aids particle dispersion and drug dissolution

Question 25

Function of flavours, colours excipients?

Answer 25

patient acceptability

Question 26

Describe tablets

Answer 26

-single dose of compressed powder
-optional coat, drug and excipients within core (matrix)
-small, portable, convenient
-very stable
-shape and colour give distinctive

Question 27

how are tablets made

Answer 27

granules or powder mixture by compression on a high speed tablet press

Question 28

what are the excipients used in tablets

Answer 28

compression aids, binders, lubricants, tablet coat, disintegrants

Question 29

function of compression aids, binders excipients?

Answer 29

bind particles under pressure to make tablets stronger

Question 30

function of lubricants excipients?

Answer 30

help tablet machine eject tablet after compression

Question 31

function of tablet coat excipient?

Answer 31

-protects contents (water, air, oxygen)
-taste masking
-identification

Question 32

Function of disintegrants excipients

Answer 32

Break the tablet up in the stomach by attracting water and making it swell

Question 33

Describe dispersible tablets

Answer 33

-dissolved in water or on tongue before taking
-very quick acting
-contain an effervescent mixture or are very thin porous tablets

Question 34

Describe immediate release tablets

Answer 34

-conventional tablets
-disintegrate and release drug in the stomach
-fast acting (<1h) if drug is quickly absorbed

Question 35

Describe delayed release tablets (gastro- resistant)

Answer 35

-intact in the stomach and disintegrate in the small intestine
-used if drug is degraded or irritates stomach
-coating is insoluble in acid (stomach) but soluble at neutral pH (intestine), called ‘enteric coating’

Question 36

Describe extended release tablet

Answer 36

-slow release drug in the GI tract over 8-24hr
-used if once a day dosing if required or fast drug release causes side effects
-tablets designed with a coating that is insoluble but porous or a matrix that erodes slowly

Question 37

Good working practice (GWP) must be followed to ensure what three things?

Answer 37

-accurate weighing of all ingredients
-no contamination
-accurate records of weighing on the BMR
(watch video on ppt for demo)

Question 38

What are the problems with powders?

Answer 38

-powder ingredients might be coarse which can lead to poor medicine stability or patient discomfort
-powder ingredients might have diff particle sizes leading to separation
-powder ingredients might need to be mixed in very different amounts. Use geometric mixing technique.

Question 39

What is the geometric mixing technique?

Answer 39

-grind a slight excess of the ingredients with bigger particles
-sieve
-weigh the powders
-Place the ingredient with the smaller volume in a mortar
-Add equal volumes of the other ingredients
-Using the pestle, mix gently until an even mixture is obtained.
-Repeat steps 5 and 6 until all ingredients are incorporated

Question 40

what are the two types of labels

Answer 40

main label and ancillary label

Question 40

general principles of labeling?

Answer 40

-clear
-printed, not handwritten
-english
-labels on medicine bottle and batch manufacturing doc

Question 40

what is the main label?

Answer 40

main source of info and allows to track the product down

Question 40

what is the ancillary label?

Answer 40

warning and advisory labels- legal requirement on all medicines

Question 41

How do you name a product if the product has an official name

Answer 41

-use official name and include source at the end
-strength does not have to be included if the product can only be produced at a specific strength but must be included if more than one strength can be dispensed (check british pharmacopoeia)

Question 42

How to name a product that does not have an official name?

Answer 42

use a general name and include the strength (strength for internal medicines is expressed as the amount of drug in one dose and in external medicines, it is expressed as a percentage)

Question 43

What is dose and frequency?

Answer 43

dose- amount of medicine or drug taken on one occasion
frequency- how often dose is taken
(how to display this info on a label is on one note)