Intro to Solid Dosage Forms

Question 1

Why is there a need for dosage forms?

Answer 1

convenient and safe delivery of accurate dosage
avoiding degradation
improves palatability
form that can be administered
control drug release rate

Question 2

What is a dosage form?

Answer 2

the means/form by which drug molecules are delivered to sites of action within the body

Question 3

List off the many dosage forms.

Answer 3

tablet
capsule
solution
suspension
emulsion
powder
cream
ointment

Question 4

What must all be considered for a drug delivery system?

Answer 4

physiochemical properties (solubility, stability, etc)
biopharmaceuticals (bioavailability, etc)
therapeutics (time of onset, duration of action, site of action,
age, illness)

Question 5

What are the steps in formulation development?

Answer 5

1. pre-formulation studies
   -drug characterization
   -drug/excipient, excipient/excipient interactions
   -choice of excipients based on dosage form and drug
2. formulation
   -process variables
   -product paramters
3. testing in a biological system
   -bioavailability
   -bio distribution
   -therapeutic response
   -toxicological testing

Question 6

What are the solid dosage forms?

Answer 6

powders
capsules
tablets
modified release

Question 7

What are the advantages of solid dosage forms?

Answer 7

unit dose
cost of shipping
no breakage or leakage
masking taste is less difficult
more portable
require less space per dose
good physical and chemical stability
elegant distinctive appearance

Question 8

What are the disadvantages of solid dosage forms?

Answer 8

potential bioavailability problems
potential irritant effect on GI mucosa
occasional difficulty in formulation
manufacturing can be technical/specialized

Question 9

What are the three steps that drugs undergo?

Answer 9

disintegration
dissolution
absorption

Question 10

What are the excipient categories of tablets and capsules?

Answer 10

diluent
binder
disintegrant
lubricant
glidant
coloring agent
plasticizer

Question 11

What are the excipient categories of oral liquids?

Answer 11

pH modifier
wetting/solubilizing agent
antimicrobial preservative
chelating agent
antioxidants
sweetening agent

Question 12

What are the excipient categories of semisolids, topicals, and suppositories?

Answer 12

suppository base
suspending or viscosity agent
ointment base
stiffening agent
emollient

Question 13

What are the excipient categories of parenteral agents?

Answer 13

pharmaceutical water
diluent
tonicity agent

Question 14

What are the excipient categories of aerosols?

Answer 14

propellant

Question 15

What is bridging/arching?

Answer 15

material being discharged or fed forms a bridge/arch over the feed auger or discharge point in a cone or hopper
forces acting on the particles at the wall equal the internal strength of the mass of powder particles
no flow condition

Question 16

What is the solution to arching?

Answer 16

larger discharge output
-success is limited with sticky fine powders

Question 17

What is rat-holding?

Answer 17

material forms a hole or narrow channel above the feed auger or outlet in a hopper while the remaining material is stationary against the hopper wall
no flow condition

Question 18

What is seggregation?

Answer 18

particulate solids and also quasi-solids tend to segregate by virtue of differences in size and physical properties

Question 19

True or false: there is a direct relationship between particle size and chemical, physical, and pharmacological properties of a drug substance

Answer 19

true

Question 20

What is dissolution rate?

Answer 20

the rate at which the particle dissolves
-smaller particles have a higher dissolution rate

Question 21

How might one increase the bioavailability of a poorly soluble drug?

Answer 21

increase surface area

Question 22

What is suspendability?

Answer 22

ability of a particle to remain undissolved but uniformly dispersed in a liquid vehicle
-larger particles settle faster
-smaller particles settle slower

Question 23

What are all the possible characteristics that particle size can influence?

Answer 23

dissolution rate
suspendability
accuracy of dosage form
penetrability
non-grittiness
chemical stability
flowability
compressibility

Question 24

What is penetrability?

Answer 24

the ability of a particle to reach their intended location

Question 25

Why is non-grittiness important?

Answer 25

we dont want solid particles in dermal product to feel gritty
finer particles allow for smoother texture, appearance, and flow

Question 26

What is chemical stability?

Answer 26

refers to degradation reactions
-smaller particles have larger surface area=vulnerable to
reactions with oxygen, water, and light

Question 27

What is flowability?

Answer 27

effect on flow properties of powders and mixing of powders and granules
important in manufacturing of tablets and capsules

Question 28

What is compressibility?

Answer 28

effect on adhesion when compressing granules into tablets
important in manufacturing of tablets and capsules

Question 29

What are the advantages of sieving?

Answer 29

inexpensive
simple
fast

Question 30

What are the disadvantages of sieving?

Answer 30

does not provide as much information as microscopy

Question 31

What is the difference between monodisperse powders and polydisperse powders?

Answer 31

monodisperse: powders containing particles of uniform size (rare)
polydisperse: particle size varies a great deal

Question 32

What is communition?

Answer 32

mechanical process of reducing particle size of a solid substance to a finer state of subdivision
-small scale or industrial

Question 33

What is small-scale communition?

Answer 33

involves the use of a mortar and pestle by pharm or tech
-trituration, levigation, pulverization by intervention

Question 34

Explain trituration.

Answer 34

the process of grinding a drug in a mortar to reduce its particle size

Question 35

Explain levigation.

Answer 35

the process of mixing a powder with a liquid or semi-solid vehicle, in which the powder is insoluble, to form a smooth paste

Question 36

Explain pulverization by intervention.

Answer 36

particle size reduction with the aid of an additional material, which can later be removed

Question 37

What is milling?

Answer 37

industrial scale or mechanical process of reducing particle size

Question 38

What are the three broad categories of milling equipment?

Answer 38

coarse crushers (jaw, roll, and impact crushers)
intermediate grinders (hammer, roller, rotary cutters)
fine grinding mills (ball, hammer, colloid, fluid energy mills)

Question 39

Why is it important to thoroughly mix powders?

Answer 39

essential to ensure uniformity of drug throughout a batch and between batches

Question 40

What are the three methods of small-scale extemporaneous mixing?

Answer 40

trituration: using mortar and pestle and mixing in a single op
spatulation: blending powders with a spatula on a tile or paper
sieving: used to help reduce loosely held agglomerates or to
increase effectiveness of blending

Question 41

What is a powder?

Answer 41

mixture of dry, finely divided drugs and or chemicals that may be intended for internal or external use
-basic formulation
-mostly replaced by tablets or capsules

Question 42

What are the uses of medicated powders?

Answer 42

oral: usually after mixing in water, preferred by people who
cant swallow other solid dosage forms
topical powders: external application to the skin, most powders

Question 43

What are the advantages of powders?

Answer 43

flexibility in compounding
suitable for infants and young children
rapid onset of action (no disintegration)
can be applied to many body cavities
good chemical stability

Question 44

What are the disadvantages of powders?

Answer 44

potential for misunderstanding for method of correct use
bitter or unpleasant taste
difficult to protect hygroscopic or aromatic material from degradation
time-consuming to prepare uniform wrapped doses

Question 45

What are some “other” bulk powders?

Answer 45

dusting powders (usually topical)
dentifrices (denture powders, dental cleaning powders)
douche powders (dissolved in water prior to use as antiseptics)

Question 46

Describe bulk powders for oral use.

Answer 46

convenient for dispensing non-potent, powdered drugs, which have doses that require large volumes
dose is measured volumetrically by patient or care-giver
not appropriate for drugs that require accurate dosing