Pharmaceutics II (solid dosage forms, Test 1) Flashcards

Terms Definitions
2 of the most popular solid dosage forms?
tablets and capsules
What percentage of U.S.'s drugs are formulated in oral dosage forms?
What is a tablet?
a solid pharm. dosage form containing drug subst.s with or without suitable diluents
Describe physical traits of tablets?
vary in size, shape, wt.,hardness, thickness, disintegration, and dissolution characteristics
Tablets are mostly used how?
How are tablets primarily prepared?
by compression with a very few prepared by molding
4 pros of tablets?
1. cheap to make2. easy to make and ship3. accurate dosing4. easy to administer
2 general ingredients of tablets?
1. active ingredient 2. excipients (adjuvants)
What is an adjuvant?
a component added to an active ingredient that has a special function (to form a tablet)
What is a diluent?
(filler)...adds bulkiness to the formulation to prep. tablets of desired size
4 examples of tablet diluents?
1. lactose2. sucrose3. mannitol4. starch
What are binders?
(adhesives)...promotes adhesion of the particles in the formulation, helps in granulation and maintain integrity of the final tab.
3 ex.s of binders?
1. starch paste2. alcohol3. water
What is a disintegrant?
promotes the breakup of the tablet (and capsule "slugs") into smaller frag.s in an aqueous environ. thereby increasing the available surface area and promoting a more rapid release of the drug substance
2 examples of disintegrants?
1. pregelatinized starch2. microcrystalline cellulose
What are super disintegrants?
disintegrate in less time...b/c of the increased demands for faster dissolution reqt.s, these are now available
3 super disintegrants?
1. modified starches2. cross-linked polyvinylpyrrolidone3. modified cellulose
Describe the super disintegrant "modified starches"?
-sodium carboxymethyl starch...chemically treated potato sodium starch glycolate
Describe the super disintegrant "cross-linked polyvinylpyrrolidone"?
water insoluble and strongly absorbs water and can crospovidone
Describe the super disintegrant "modified cellulose"?
internally cross-linked form of sodium carboxymethyl Ac-Di-Sol (accelerates dissolution)
What are lubricants?
agents added in small qtys to tablet and capsule formulations to improve certain processing characteristics
3 roles identified with lubricants?
1. true lubricant role2. anti-adherent role3. glidant role
What is the True-Lubricant Role of lubricants?
to decrease friction at the interface between a tablet's surface and the die wall during ejection and reduce wear on punches and dies
What is the Anti-adherent role of lubricants?
prevent sticking to punch faces or in the case of encapsulation
What is the Glidant role of lubricants?
enhance product flow by reducing interparticulate friction
5 examples of lubricants?
1. calcium stearate2. zinc stearate3. starch4. talc5. magnesium stearate
Which is one of the most widely used lubricants in the pharmaceutical industry? Why is a very low concentration reqd when using it?
Magnesium stearate is hydrophobic, so just use a small concentration or tablet will not dissolve
Describe the process of tablet dissolution?
1. Tabs (or caps) EITHER disintegrate to form granules or aggregates OR they dissolve into solution and then can go on to be absorbed2. Granules or aggregates EITHER deaggregate into fine particles OR the dissolve into solution and can go on to absorption3. The fine particles dissolve into solution and then can go on to absorption
What is the rate limiting step of the dissoltion process?
the dissolution of drug into solution...this is reqd for drug to absorb
Where does dissolution occur typically?
in the stomach or intestinal fluid
12 types of tablets?
1. compressed tabs2. multiple compressed tabs3. sugar coated tabs4. film coated tabs5. gelatin coated tabs6. enteric coated tabs7. buccal and sublingual tabs8. chewable tabs9. effervescent tabs10. molded tabs11. vaginal tabs12. rapidly dissolving tabs (RDT)
What does RDT stand for?
rapid dissolving tab
What does buccal refer to?
What does sublingual refer to?
under the tongue
What are the most common type of tablets?
compressed tablets
General process for preparing compressed tabs?
1. Active ingredients and Adjuvents (excipients) are mixed and granulated2. drying3. pressing4. coating (if applicable)5. packaging
What are adjuvents?
excipients, or ingredientss to bind active elements together
What are multiple compressed tabs?
tabs subjected to more than single compression
What do multiple compressed tabs result in?
a tablet core and shell, or layered tabs
What is the purpose of multiple compressed tabs?
to solve incompatibility issues (2 incompat. drugs in one tab) or for controlled release
Multiple compressed tabs have a unique what?
What do sugar coated tabs have?
water soluble sugar layer that quickly dissolves in the GIT
2 advantages of sugar coated tabs?
1. protection from the environement2. mask taste and odor
What are 2 diadv.s of sugar coated tabs?
1. time consuming (long process, many coats applied)2. increase tab wt. and shipping costs
6 steps of sugar coating tablet preparation?
1. waterproofing2. subcoating3. smoothing and final rounding4. finishing and coloring5. imprinting6. polishing
Explain the 1st step of sugar coating, waterproofing?
takes place in a coating pan...done to protect moisture...includes 1 or more layers...shellac or polymer in alcohol (poured or sprayed)...warm air for drying
Explain the 2nd step of sugar coating, subcoating?
involves 3-5 coats...sugar based syrup with gelatin, or acacia, or PVP...rounding the tab and bond the sugar coat to the tab.
Describe the 3rd step of sugar coating, smoothing and final rounding?
5-10 addnal coats or thick syrup...mainly sucrose based...warm air
Describe the 4th step of sugar coating, finishing and coloring?
coat with thin syrup and color to attain final smoothness
Describe the 5th step of sugar coating, imprinting?
printed, or engraved
Describe the 6th and final step of sugar coating, polishing?
carnuba wax and/or beeswax
Describe thin-coated tablets?
have a thin skin-tight coating of a plastic like material...have the same wt., shape, and size of the original uncoated tab
Film coated tabs are resistant to what?
The coating solution of film coated tabs is either ? or ?.
aqueous or nonaqueous
The film coating of tabs takes place in a what?
coating pan
The solvent for an aqueous film coating vs nonaqueous?
aqueous = waternonaqueous = alcohol-acetone
The film forming polymer of an aqueous film coating vs nonaqueous?
aqueous = methylcellulosnonaqueous = cellulose acetate phthalate
What does a plasticizer do?
increases flexibility
The plasiticizer of an aqueous vs. nonaqueous film coating?
aqueous = glycerinnon = castor oil
Gelatin coated tabs facilitate what?
Where are gelating coated tabs mainly seen?
prenatal vit.s
gelatin coated tabs are ? evident and has ? size than equivalent capsule.
are tamper evident...has smaller size
What are enteric coated tabs intended to do?
to pass thru the stomach intact to disintegrate and release their drug content for absorption along the to dissolve at a pH > 4.8
The coating system for an EC tab may be what?
either aqueous or organic (nonaqueous)
2 materials used in EC coated tabs?
1. Shellac2. cellulose acetate phthalate
Buccal and sublingual tabs have no what?
no first pass effect (they go straight into circulation)(so all of the drug is absorbed
What does the first pass effect refer to ?
the fact that most oral tabs lose ~50% of their strength when they pass thru the liver
Rate of absorption for buccal and sublingual tabs?
Why would buccal and sublingual tabs be desirable for rapid absorption?
they are dissolved in areas having good blood supply (under the tongue has many blood vessels)
Ex. of a sublingual tab?
nitroglycerin tabs
Buccal and sublingual tabs have no?
Describe chewable tabs?
have smooth and rapid disintegration when chewed or allowed to dissolve in the mouth. Have a good taste and texture.
2 examples of chewable tabs?
Antacids, Kids multivit.s
Is chewing of chewable tabs reqd?
How much pressure is used when compressing chewable tabs?
minimal (this is why they can dissolve in mouth)
A chewable tab may contain up to 50% of what?
Chewable tabs are good for what?
large tabs or tabs for kids (often come in fruit flavors)
An advantage of chewable tabs?
admin. of lg tabs to children and elderly who have difficulty swallowing
How are effervescent tabs prepared?
by compressing granular effervescent salts that release gas when in contact with water
What important ingredients are in effervescent tabs?
sodium bicarbonate and the organic acids (tartaric acid and citric acid)
What does tartaric acid do for effervescent tabs?
produces fragile granules
What does citric acid do for effervescent tabs?
produces sticky granules
What occurs when effervescent tabs are in the presence of water?
the additives (sodium bicarb, tartaric acid, and citric acid) react, releasing carbon dioxide that acts as a disintegrator and produces effervescence
What is the advantage of the effect of effervescence?
(from the CO2) kind of numbs the tongue and masks the taste
Molded tabs are prepared on what? What are they intended for?
a small lab scale...made in a mold and intended for rapid dissolution upon administration
Molded tablets basic ingredients?
drug + base
The Base in molded tablets is usually what?
lactose + sucrose 5-20%
When preparing molded tabs the powder mixture is wetted with what?
wetted with a 50% mixture of water and alcohol sufficient only to dampen the powder to be compacted
hardness of a molded tab?
molded tabs are soft
Describe vaginal tabs?
1. uncoated, bullet or ovoid shaped tabs2. for local effect3. shaped to fit snugly on plastic inserter4. typically antibacterial for vaginitis
How quickly does an RDT dissolve?
dissolves in the mouth 10sec -1min
3 Adv.s of RDTs?
1. quick onset of action with some drugs2. easy for kids and elderly3. administration easier than oral liquid
5 disadv.s of RDTs?
1. difficulty in drug loading2. taste masking is difficult because there are not a lot of additives3. manufacturing cost4. stability of products5. friability
What does friability refer to?
how easily a tab can break
Name the 2 preparation techniques for RDTs?
1. lyophized (freeze-drying)2. compression
Describe the technique of lyophized (freeze drying) RDTs?
tabs are prepped by foaming a mix of gelatin, sugar, drug, and other ingredients and pouring the foam into a mold
How is a lyophized RDT like a tab?
fragile porous
How is a lyophized RDT packaged?
in a blister pack
How quickly does a lyophized RDT disintegrate?
within seconds
2 examples of lyophized RDTs using Zydis technology?
1. loratadine (claritin reditabs)2. zofran ODT
What kind of technology does the prep of RDTs by compression use?
standard tableting technology
Which is more fragile, Lyophized RDTs or Compressed RDTs?
Which takes longer to dissolveLyophized RDTs or Compressed RDTs?
compressed...take a few seconds longer
The method of compression for RDTs makes use of what?
Compressed RDTs frequently include what excipients?
effervescent excipients
Compressed tabs are thinner than regular tabs for what reason?
to provide a lg surface area
Ex. of a compressed tab prepped by OraSolv and DuraSolv technology?
7 aspects of a dosage form that may be tested?
1. wt. variation2. content uniformity3. tablet thickness4. hardness5. friability6. tablet disintegration7. dissolution testing
Wt. variation in dosage testing refers to what?
wt of each tab
content uniformity in dosage form testing refers to what?
amount of active ingredient in each tab...each tab must fall within range of 85%-115% of label claims...RSD < 6%
4 things that determine the thickness of a tablet?
1. the diameter of the die2. the amount of fill permitted to enter the die3. the compaction forces (micrometers)4. the force or pressure applied during compression
Hardness in dosage form testing refers to what?
the force needed to break the tablet...affects dissolution
What is a friability test?
wt. lost on exposure to slow rotation, weighed before and after...resistance to wt loss is an indicator of tabs ability to withstand abrasion in handling, packaging, and shipment.
What is used to conduct a friability test?
a friabilator
What is the accepted wt. loss for a tab in a friability test?
< 1%
How is tablet disintegration tested?
in a machine that simulates gastric fluid and mimics body temp of 37 degrees celsius...10 tabs are tested
How long should an uncoated tab take to disintegrate when tested?
30 minutes
How long should a sublingual tab take to disintegrate when tested?
2 minutes
What does SGF stand for?
simulated gastric fluid
What is dissolution testing?
making sure drugs dissolve in fluids...involves a paddle or basket
What is the importance of dissolution testing?
product optimization...QA in production...BIOEQUIVALENCE INDICATION (for generics to a brand name)...FDA reqt for marketing
Temp. at which a dissolution test takes place and the amount of fluid involved?
37 degrees celsius, 900 mL
6 factors effecting disintegration and dissolution?
1. particle size2. hygroscopicity3. type and conc. of disintegrant4. binder and lubricant5. manufacturing method6. compression force
How is particle size related to disintegration and dissolution?
a decreased part. size = increased disintegration
What does hygroscopicity refer to?
ability to absorb water
An example of a lubricant?
magnesium stearate
How is compression force related to disintegration and dissolution?
increased force = harder = decreased disintegration
What are granules?
prepared agglomerates of smaller particles of powder
In what size range do granules fall?
4-12 sieve size range
How do granules flow compared to powder?
well (think of granulated white sugar vs. powdered)
Why are granules commonly used in tableting?
to facilitate flow of material from hopper (feeding container) into tablet press
Granules are more stable than powders when it comes to what?
to atmospheric effects of humidity due to smaller surface, oral antibiotics for reconstitution
What are easier to wet, granules or powders?
The 2 methods of granulation?
1. wet granulation2. dry granulation
Why granulation?
an important reqt in tablet manufacturing is that the drug mix should flow freely from the hopper of the tablet press into the dies to enable high speed compression of the powder mix
7 steps of wet granulation?
(widely used method)1. weighing and blending ing.s2. prep damp mass3. screening into pellets or granules4. drying the granules5. sizing the granulation by dry screening6. adding lubricant and blending7. compressing tabs
In dry granulation what is done to the powder mix?
is is compacted in large pieces and subsequently broken down into granules
In dry granulation either the active ingredient or the diluent must have what?
cohesive properties
When is dry granulation used?
when wet granulation is not possible due to moisture sensitivity or heat sensitivity
6 steps of dry granulation?
1. weighing the ing. mix2. slugging or compressing into flat tabs or pellets 1 inch diameter3. slugs are broken up by hand or mill4. passed thru screen5. lubricant is added6. tab is compressed
When would direct compression be used?
in some meds (KCl) that have cohesive and free flowing properties
When using direct compression excipients with cohesive properties should be used for what reason?
to allow tabs to be compressed withoout granulation
When using direct compression what is the filler?
spray dried lactose, microcrystalline cellulose
What is the disintegrant in direct compression?
direct compression starch cross linked CMC, cross linked PVP
Some problems in tab manufacturing?
capping/lamination...splittig of the tabs or layering...related to air entrapment in the tablet especially during COMPRESSION (causes tab to be friable)
4 contributors to problems in tab manufacturing?
1. air2. high speed production (don't have enough time for bonding)3. non-clean, or non-smooth punches (like if you don't use enough glidant)4. granules with great portion fines (like powdered sugar)
What are capsules?
a solid dosage form in which meds or inert substances are enclosed in hard or soft gelatin caps
How are caps taken?
usually intact but may be opened and mixed with liquid or food under a pharm.s supervision
What dosage is used during clinical trials?
Two types of capsules?
1. hard gelatin2. soft gelatin
Hard gelatin caps consist of what?
cap and body : cap slides over base
What is an empty hard gelatin cap shell made out of?
gelatin, water, sugar, dye, titanium dioxide
Percentage of moisture in hard gel cap shell?
13-16% moisture
How should hard gelatin caps be stored?
at cond's of intermediate humidity
What could occur if a hard gelatin cap is stored at high humidity?
dissolution time may increase
Where do hard gelatin caps dissolve and expose their contents?
dissolve in HOT water and in warm gastric fluid, and exposes its content in GIT
Why does gelatin get digested in GIT?
because it is a protein
4 different capsule shapes?
1. Coni-snap cap2. pulvules3. spansules4. kapseal
Describe a Coni-snap capsule?
has grooves to lock the body and the cap and a curved rim to prevent denting and splitting problems that are common with straight rims
Describe shape of pulvule caps?
one end tapered
Describe shape of spansule caps?
sharp pointed ends
Describe shape of kapseal caps?
colored band surrounds the joint b/n cap and body
Describe cap size?
human size ranges from 5 to 000 with 5 being the smallest and 000 being the largest
How much powder can a cap accomodate?
65 mg to 1g of powder (depends on the wt and density)
What size cap should you use when making a drug?
the smallest size that will hold your content
The composition of caps is similar to what?
2 general things caps are composed of?
1. active drug2. excipients
Describe 4 possible excipients of capsules?
1. diluent (may be added...such as lactose or microcrystalline cellulose)2. disintegrant (like starch, sometimes added to enhance the powder break up and spreading after shell opening in stomach3. Glidant and/or lubricant (silicon dioxide or mg stearate)4. surfactant (Na lauryl facilitate wetting of the cap content by the GI fluid
For uniform drug distribution in caps you would use what?
similar density excipients if possible and particle reduction
3 methods of cap filling?
1. the punch method2. hand operating machines fill3. on large scale
3 methods of cap sealing?
1. sometimes colored band of gelatin used2. heat welded3. liquid and low heating
Once finished a cap is often covered in powder, how is it cleaned?
vacuum, individually
What is a soft gelatin cap shell made of?
1. gelatin2. polydydric alc. as sorbitol or glycerin to make it more elastic3. water...higher percentage than hard shell4. preservative (because it has a larger percentage of water) (like methylparaben)5. only commercially prepared
3 things soft gel caps can be filled with?
1. liquid, pastry and dry fills2. solids (in solution, suspension,dry powder, pellets, small tabs)3. liquid (water immiscible volatile and nonvolative oils, water miscible non-volatile liquids like PEG)
What liquids cannot be filled in soft caps?
liquids with water >5%, or low MW volatile organic compound as alcohol
How do you test for disintegration of capsules?
capsule in basket at 37% C...capsule has to disint. to soft mass
How do you test for dissoluton of caps?
capsule may be tested intact or emptied if gelatin interferes with test
How do you test for dosage form unity of caps?
wt variation and/or content uniformity
How does wt variation of hard gel caps test for dosage form uniformity?
10 caps are indiv. weighed INTACT and the EMPTIED SHELLS to determine the content
How does wt variation of soft gels test for dosage form uniformity?
INTACT and EMPTIED caps after washing
What is content uniformity?
determination of the active ingredient content in the cap
Unless otherwise indicated within what range should the ACTIVE INGREDIENT AND THE WT VARIATION fall within for the first 10 caps tested?
How is the stability of a cap tested?
stab. of the active ing. and well as the effect of temp, humidity, and light on the to accelerated stability studies
How are caps orally administered?
with water...if need to be opened it should be done under a pharmacist's supervision
Capsule's relevance to food is what?
very important whether to take with or without food
/ 185

Leave a Comment ({[ getComments().length ]})

Comments ({[ getComments().length ]})


{[ comment.comment ]}

View All {[ getComments().length ]} Comments
Ask a homework question - tutors are online