Dosage Tablet
How do processing factors affect dissolution rate?
-Wet granulation improves dissolution -Compression force affects hardness
What are the advantages of fast-dissolving tablets?
-easy to take -fast acting
What are the advantages of oral tablets
1. Low cost of production 2.easy to package 3.stability (solid state) 4.tamper-resistant 5. patient acceptance(most common form)
What are disadvantages of oral tablets
1.Limited dosage flexibility 2.complex formulation requirements (needs to be hard but dissolve fast) 3. esophageal adhesion
What are benefits of tablet coating
1.Protect ingredients from oxidation 2.mask taste 3.help swallowing 4.tablet identification 5. durability
What is the general purpose of basket rack assembly
1.Simulates body conditions of gastric fluids 2. Determines time of complete disintegration
What is the recomended amount of liquid one should take to avoid esophageal adhesion?
100ml
How long should it take to dissolve 75% of the drug?
45mins
What does the process begin with when making tablets
A powdered form
Why are tablets coated
After compression tablet core is too rough
What are put in place to ensure uniformity of active ingredients among tablet batches
Assays
What apparatus is used in disintegration tests
Basket rack assembly
With coding what do we look at to ensure the quality of compressed tablets
Bed paint job non-elegant= MOTTLING
What are the steps were wet granulation
Blending>wettin>granulation> drying >sieving> blending(lubricant Glidants disintegrate)>compression
How do disintegrates work
By wicking or drawing in G.I. fluids
With appearance what do we look at to ensure quality of compressed tablets
Capping indicates compression problems. (splitting the from trapped air or uncleaned punches)
What is gelatin coating
Capsule shaped tablet with gelatin coating
What is an example of a gliding
Colloidal silica
what is direct compression
Compressing tablets directly from powdered material
How are tablets prepared
Compression of powders or granules into hard masses
What is an example of a disintegrant
Corn starch cellulose
What is an example of an adhesive
Cornstarch,providone, cellulose
What test is done for bioavailability of the tablet
Disintegration test (how well the tablet falls apart)
How are effervescent tablets meant to be taken?
Dissolved prior to ingestion (alka setlzer)
What do US P test include
Drug content (how much )drug release (disintegration)
If this integration is a complete within 30 minutes what happens
Drug is been moved to intestinal fluid conditions
What makes a direct compression difficult
Drugs are not easily compressible usually need special excipients
Why do we use water for neutral drugs?
Drugs dissolve where it ionizes!!! If no ionizable group, water is used
Why are fillers important
Drugs less than 70 mg are hard to pick up
What is an example of a drug that needs enteric coating
Erythromyosin undergoes acid catalyzed hydrolysis
Which type of drug disolves in the mouth without the need for chewing?
Fast-dissolving tablets
How does tablet formation affect dissolution rate?
Fillers = hydrophilicity of diluent affects penetration Magnesium Stearate = forms water repellent coat (limits wetting)
What approach of coding is more modern and most common
Film
Powder is a must have two properties to make a tablet, what are they
Fluidity (so it can flow into the die )compressibility ( remain stable one pressures applied)
What is granulation
Formation of granules
When is measuring drug content uniformity most important
Four tablets that are less than 50 mg where most of the drug is excipients
What improves powder fluidity
Glidants, lubricants and granulation
Tablets are manufactured at high speeds which causes what?
Good cost efficiency
What improves compressibility of powders
Granulation
What are examples of medium for basic drugs?
HCl (protonation in stomach)
What is hardness measured by
Hardness tester which measures crushing strength
What is a tablet
Hey disc like mass of medicinal powder
Why do we test for hardness
If too hard will not disintegrate if too soft will not hold together
Does increase surface area increase or decrease drug dissolution
Increases
A punch that has a raise causes what
Indentation in tablet
Why are pH sensitive polymers used to coat tablets
It increases solubility in both acidic and basic environments
What do adhesives do
Keeps tablet together
What is an example of a filler
Lactose cornstarch
Dissolution is an important test for which kind of drug?
Limited water solubility
US P test are good for assessing drug content uniformity if the tablet has high or low excipient fraction
Low the tablet is mainly the drug
What is an example of a lubricant
Magnesium stearate, talc
How can you tell if a tablet is sugarcoated
Name is painted on and very smooth no indentation
Do drugs usually have both good cohesive and flow properties
No
Does the entire tablet court need to be enteric-coated
No Prevacid has only granules coated
What is the definition of complete disintegration
No palpably firm core
With disintegration tests do you have to assay the drug?
No with dissolution test you have to
Why do we form granules
Prevents stratification(granules are uniform) improves fluidity(granulated sugar vs powdered) improves compressibility
What is the paradox for compressed tablets
Produce strong tablets yet fast breakdown
Why is aspirin coated
Protects stomach from irritation
What are the two methods for testing dissolution?
Rotating basket (placed in basket and rotated at fixed speed) Paddle method (dosage sinks to bottom of vessel and medium is agitated)
Why is direct compression used
Simple.(mainly for drugs with good cohesive and flow properties)
What characteristics do tablets vary in
Size shape color disintegration and usage
If a tablet has less pores, will it disolve faster or slower?
Slower! cannot draw in water
How are dry granules formed
Slugging large masses of drugs followed by milling
How is a tablet film coated
Spraying a thin film of polymer solution around tablet core leaving indentations and scores
Which coating method is the oldest
Sugar
What are the different types of coating
Sugar film gelatin enteric
What is a dissolution test?
Test done to measure the rate of the drug to go into solution
What does friability measure
The tendency of a tablet to crumble
What other characteristics do we look at to ensure the quality of compressed tablets
Thickness hardness friability
What is the main purpose of disintegrants
To bring water into the tablet
What is the main purpose of glidants
To fill in crevices making it smoother
Why are enteric coatings used
To prevent tablet core from disintegration in ACIDIC environment
How are tablets compressed?
Using high pressures with a tablet punch
What type of medium is used in dissolution tests?
Weak acids= intestine environment
How does drug uniformity differ with large amounts of excipients
Weight of tablet can be the same but uniformity may change
Why does US P test for drug content
Weight variation and uniformity of a batch
What is the most common approach to tablet production
Wet granulation (dough)
When is dry granulation you
With the moisture or heat sensitive ingredients
What are examples of medium for acidic drugs?
buffer at 7 pH (deprotonation in intestine)
What type of tablet is intended to distegrate in the mouth?
chewable tablets
Which type of drug usually has no distegrant?
chewable tablets
What is an example of a lozenge?
cough drop (stays for a while)
What are the two excipients used in wet granulation
dilutent =for size adhesive= binding agent Lubricant= prevents granules from sticking to surface Glidants= improves flow Disintegrants= helps GI gain access to drug
If solubility is the rate limiting step which test do you have to perform?
dissolution (if the drug dissentegrates, awesome, but if it doesnt dissolve it will not enter the body)
Why is the claim "fast acting" not always true in fast disintegration tablets?
dissolution may be the rate limiting step if the particles are coated
Storing at room temp and away from humid areas helps what?
dissolution stability
What type of drug is made with salt mixtures and produces CO2?
effervescent tablets
It is important to not crush or chew which kind of coating?
enteric
Why must fast dissolving tablets be well protected?
high exposed surface area
What can esophageal adhesions cause?
irritation and ulceration
What type of tablet is intended to disolve slowely for a local effect?
lozenges
What factors influence a drugs adhesion?
shape, size, surface (sticky), patient position, volume of water, diseases (diabetes or alcholism)
What are eamples of medium for neutral drugs?
water
How can you help swallowing of capsules?
wet with water or saliva?