Intro to Solid Dosage Forms Flashcards
Why is there a need for dosage forms?
convenient and safe delivery of accurate dosage
avoiding degradation
improves palatability
form that can be administered
control drug release rate
What is a dosage form?
the means/form by which drug molecules are delivered to sites of action within the body
List off the many dosage forms.
tablet
capsule
solution
suspension
emulsion
powder
cream
ointment
What must all be considered for a drug delivery system?
physiochemical properties (solubility, stability, etc)
biopharmaceuticals (bioavailability, etc)
therapeutics (time of onset, duration of action, site of action,
age, illness)
What are the steps in formulation development?
- pre-formulation studies
-drug characterization
-drug/excipient, excipient/excipient interactions
-choice of excipients based on dosage form and drug - formulation
-process variables
-product paramters - testing in a biological system
-bioavailability
-bio distribution
-therapeutic response
-toxicological testing
What are the solid dosage forms?
powders
capsules
tablets
modified release
What are the advantages of solid dosage forms?
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
What are the disadvantages of solid dosage forms?
potential bioavailability problems
potential irritant effect on GI mucosa
occasional difficulty in formulation
manufacturing can be technical/specialized
What are the three steps that drugs undergo?
disintegration
dissolution
absorption
What are the excipient categories of tablets and capsules?
diluent
binder
disintegrant
lubricant
glidant
coloring agent
plasticizer
What are the excipient categories of oral liquids?
pH modifier
wetting/solubilizing agent
antimicrobial preservative
chelating agent
antioxidants
sweetening agent
What are the excipient categories of semisolids, topicals, and suppositories?
suppository base
suspending or viscosity agent
ointment base
stiffening agent
emollient
What are the excipient categories of parenteral agents?
pharmaceutical water
diluent
tonicity agent
What are the excipient categories of aerosols?
propellant
What is bridging/arching?
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
What is the solution to arching?
larger discharge output
-success is limited with sticky fine powders
What is rat-holding?
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
What is seggregation?
particulate solids and also quasi-solids tend to segregate by virtue of differences in size and physical properties
True or false: there is a direct relationship between particle size and chemical, physical, and pharmacological properties of a drug substance
true
What is dissolution rate?
the rate at which the particle dissolves
-smaller particles have a higher dissolution rate
How might one increase the bioavailability of a poorly soluble drug?
increase surface area
What is suspendability?
ability of a particle to remain undissolved but uniformly dispersed in a liquid vehicle
-larger particles settle faster
-smaller particles settle slower
What are all the possible characteristics that particle size can influence?
dissolution rate
suspendability
accuracy of dosage form
penetrability
non-grittiness
chemical stability
flowability
compressibility
What is penetrability?
the ability of a particle to reach their intended location