Hand out and explain written assignment due for Thursday.
Discuss requirements for a drug to reach its target organs.
Using a chart of organs and blood volume, indicate that organs
differ widely in terms of proportion of systemic blood they receive, and therefore the amount of drug they will require to reach a therapeutic level.
Discuss plasma protein binding of drugs.
Indicate that drug concentration is best measured as a level of drug in the blood plasma, and can best be monitored this way.
Examine a case study involving effective dose and lethal dose levels of an imaginary drug, and why a second drug may increase the possibility of a lethal effect occurring.
List and discuss the requirement for some drugs to be introduced into the systemic circulation by other than the oral route.
Discussion reviewed the harsh conditions presented orally as well as the possible lack of bioavailability. The conditions which would require administration via ocular and otic routes discussed, as well as rectally for infants and non swallowing adults.
Session Minutes
45
Minutes Student Attended
45
Lesson Comments
Nina always has questions which lead us into very interesting discussions
Continue discussing the enteral route, the pros and cons. Discuss the first pass through the liver and view a video which illustrates it. l
Discuss the requirement of increased dosage,when orally given, to overcome the first pass.
Introduce perenteral routes of administration along with their pros and cons.
Review and discuss the biological and physical hazards that a drug must overcome just to reach the systemic circulation.
Discuss the term Bioavailability, the percent of a drug which will enter the systemic circulation compared to the dose given.
Describe the "first pass" phenomena in which the liver will detoxify all chemicals before their entrance into the blood stream.
Discuss the entereal route of administration, along with the all the chemical problems it presents.
Discuss the limits to drug bioavailability caused by systems and cells.
Discuss the factors upon which bioavailability depend.
Write the formula used to quantify availability
Start on the routes of administration of a drug, and how the route will alter the bioavailability
Begin with the enteral(oral) route and discuss the effect on systemic circulation of drugs by the first pass factor.
Session Minutes
45
Minutes Student Attended
0
Lesson Comments
Nina was to be on line for this class, however she was delayed in getting home.
Discuss the physical barriers presented by the human system to drug absorption.
Include the skin, mucous membranes, cilia, stomach acid, and intestinal alkalinity.
Indicate how these barriers will slow or stop a drug from reaching the systemic circulation.
Discuss how the bioavailability of a drug depends on it reaching the systemic circulation.
Discuss the specifics of the blood brain barrier to drugs which must reach the central nervous system.
Talk about the pros and cons of the alternate method of intrathecal injection to overcome this.
Session Minutes
45
Minutes Student Attended
45
Lesson Comments
Nina, as usual, had some very interesting questions
Discuss the types of physiological barriers to drug activity, and how these barriers operate.
View the bilayer lipid plasma membrane along with a phospholipid diagram.
introduce the hydrophilic and hydrophobic sections.
Indicate that small molecules, like steroid hormones, can pass through into the cell by diffusion.
Explain when equilibrium is reached in the diffusion process.
indicate that water soluble drug molecules will have a more difficult time passing through the membrane, and require speciric proteins to pass them through.
Read a case study and discuss the cause and effect and possible reasons for the cause.
Discuss how some drugs with promising pharmacological therapies might fail in human clinical trials.
Discuss factors which would preclude a drug from reaching its target organ, at a concentration efficient to exhibit a therapeutic response.
Discuss these as absorption, distribution, and metabolic factors
Discuss human double blind studies and animal studies
Session Minutes
45
Minutes Student Attended
45
Lesson Comments
Nina always has such interesting questions and points.
Discuss the difference between quantal relationships and graded dose responses. Quantal includes the effect on a population.
Discuss and define effectiveness (ED50) toxicity (TD50), and lethality (LD50).
Show the differences as seen on a graph
Discuss therapeutic range of doses, and what can happen if the lethal dose 50 is very close to the therapeutic dose 50.
