Lecture 9 Oral Drug Delivery Flashcards
Describe the advantages and disadvantages of oral drug delivery.
Advantages include acceptability, compliance, ease of administration, bioavailability, and improved efficacy.
Disadvantages may involve adverse environmental factors and difficulty swallowing.
What is the role of Modulated Release (MR) in drug delivery?
MR helps modulate drug absorption and alter the site of release, leading to improved efficacy, reduced adverse events, increased convenience, compliance, and optimized performance.
How does drug release in Modulated Release (MR) systems vary based on dissolution?
In MR systems, drug release is influenced by factors like the type of polymers used (such as HPMC and HPC), molecular weight, viscosity, hydration rate, and solubility.
Define the diffusion mechanism in Modulated Release (MR) systems.
In MR systems, diffusion involves the drug diffusing through polymers like EC, with factors such as lipophilicity, molecular weight, and viscosity affecting the process.
What are the characteristics of polymers commonly used in matrix systems for oral drug delivery?
Polymers used in matrix systems are hydrophilic, robust, and flexible, making them popular for extended release formulations. These polymers are typically water-soluble, gel-forming, and/or swellable.
Describe the process of tablet ingestion and drug release in the context of the provided content.
Ingestion of tablet leads to initial wetting, followed by the expansion of the gel layer, tablet erosion, and the release of both soluble and insoluble drugs.
Define HPMC in the context of the provided content.
HPMC is a hydrophilic polymer that forms a gel layer in contact with water, regulating the dissolution of the tablet and changing the drug release profile.
How does the Korsmeyer-Peppas equation contribute to the field described in the content?
The Korsmeyer-Peppas equation is used to model in vitro drug release, providing a mathematical framework to understand and predict the release kinetics of drugs from formulations.
Do the physical properties of the gel layer change over time in the described process? If so, how?
Yes, the dry core of the tablet becomes smaller over time while the gel layer becomes bigger. This change leads to a more relaxed structure, resulting in the release of more drug.
Describe the role of the gel layer formed by the hydrophilic polymer in controlling drug release.
The gel layer formed by the hydrophilic polymer controls fluid ingress and the mechanism of drug release, regulating the dissolution of the tablet and influencing the release profile of the drug.
