29 Questions
What is one of the advantages of the oral route for drug delivery?
Larger surface area of the GI compared to other transmucosal routes
Why is the specialized columnar epithelium of the GI tract conducive to drug absorption?
It allows for rapid absorption of drugs with appropriate physicochemical characteristics
How does the rich blood supply of the GI mucosa contribute to drug delivery?
It ensures rapid drug absorption and onset of action
Why does the oral route allow for improved compliance?
It enables self-administration and is noninvasive
How do controlled-release (CR) dosage forms impact dosing schedules?
They can eliminate the need for frequent daily-dosage regimens
What characteristic makes the oral route usually the safest and least expensive route for drug delivery?
It allows for self-administration and is noninvasive
What is a significant benefit of the oral route for drug delivery?
Amenability to immediate release (IR)
What is a function of the pancreatic enzymes in the small intestine?
Digestion of proteins, carbohydrates, fats, and nucleic acids
What is a role of the GI mucus layer in oral drug delivery?
Acts as a physical barrier hindering drug diffusion to the absorbing surface
What is a limiting factor for oral drug delivery associated with the P-Glycoprotein Efflux Pump?
Functions as an energy-dependent, drug efflux pump at the apical surface of cells
What pH range is observed in the duodenum along the GI tract?
4 to 5
What is one of the roles of the pH of fluids along the GI tract in oral drug delivery?
Affecting the ionization and absorption properties of the drug
Which enzyme is found in the stomach?
Pepsin
What is one function of the GI mucus layer?
Hinders drug diffusion to the absorbing surface
According to the Noyes-Whitney Rule, what is the fundamental principle for evaluation of the kinetics of drug release?
The mass transferred with respect to time by dissolution from the solid particle of instantaneous surface
What are the units in which the rate of dissolution dM/dt can be expressed for most solids?
g/(cm-2.s-1)
In which conditions is the dissolution of the solid said to be occurring under 'sink' conditions?
When Ct is less than 15% of the saturated solubility Cs
What is the effect of the prevailing concentration driving force (Cs - Ct) on the dissolution rate of the solid?
It has a negligible influence when Ct is less than 15% of Cs
What was offered by Noyes and Whitney in 1897 as the fundamental principle for evaluation of the kinetics of drug release?
The Noyes-Whitney Rule
What does M represent in the Noyes-Whitney equation: M = (S)(Cs - Ct)(dM/dt)?
The mass transferred with respect to time by dissolution from the solid particle
What is the ideal condition for the surface in the Noyes-Whitney equation?
A linear concentration gradient is confined to the layer of solution adhering to solid surface
Which model assumes that the drug is dissolved uniformly from all surfaces of the particles?
Noyes-Whitney equation
What relationship did Nernst and Brunner establish in their film theory?
$D = gSh$
What type of methods are used to investigate the kinetics of drug release from controlled release formulations?
Statistical methods, model dependent methods, model independent methods
What does the Noyes-Whitney equation assume about the particles?
They have uniform drug dissolution from all surfaces
Which equation represents the relationship between the constant and the diffusion coefficient in Nernst and Brunner's film theory?
$D = gSh$
Which category of kinetic models describes the overall release of drug from dosage forms?
Zero order, first order, Higuchi model
What are the number of kinetic models described for overall drug release?
Three kinetic models
What assumption did Noyes-Whitney Equation make about the dissolution process?
The dissolution process corresponds to a first order reaction.
Explore the advantages of the oral route for drug delivery, including its expanded surface area and accessibility for patients. Understand why the oral route is often the safest, most practical, and least expensive method of taking a drug.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
