Exam 1 Flashcards
The most important properties of an idea drug are ___, ____, and ___.
Effectiveness, safety, and selectivity
Should a drug be used if it is not effective?
No
What is the objective of drug therapy?
To provide maximum benefit with minimum harm
Drug therapy should be tailored based on what?
A client’s individual needs
If something is wrong with a prescribed drug, who is the patient’s last line of defense?
Nurse
What are the three goals of pre-administration assessment in regards to collection of data?
- Evaluation of therapeutic and adverse effect
- Identification of high-risk patients
- Assessment of the patient’s capacity for self-care
At what three levels are the analysis and diagnosis phase of treatment directed?
- Judging the appropriateness of the prescribed therapy
- Identifying potential health problems treatment might cause
- Characterizing the patient’s capacity for self-care
At what three levels is planning directed?
- Defining goals
- Establishing priorities
- Establishing criteria for evaluating success
What is the objective at the evaluation stage?
- Therapeutic responses
- Adverse reactions and interactions
- Patient adherence
- Patient satisfaction with treatment
What trial is the most reliable way to objectively assess drug efficacy and safety?
Randomized controlled trial
Phase I (subject and tests)
Subject: healthy volunteers
Tests: metabolism, pharmacokinetics, and biologic effects
Phase II (subject and tests)
Subject: patients
Tests: therapeutic utility and dosage range
Phase III (subject and tests)
Subjects: patients
Tests: safety and effectiveness
Phase IV (subject and tests)
Subject: patients
Tests: safety and effectiveness
What two groups have been excluded from drug trials?
Women and children
When working with a new drug fresh out of trial, what should you look out for?
Unreported adverse effects
Which drug name can be more beneficial in using with patient? Why?
Generic name
Brand name may not be available internationally; can be more expensive
What are the four basic processes of pharmacokinetics?
Absorption
Digestion
Metabolism
Excretion
How do drugs pass through membranes in the body?
- Pores
- Transportation
- Direct penetration
Where is P-glycoprotein found?
Liver, kidney, placenta, intestines, and brain capillaries
Where do P-glycoproteins transport drugs to?
OUT of the cell
Which drugs can pass through the lipid bilayer of a membrane easily?
Lipid-soluble drugs
In what type of media do acidic drugs ionize?
Basic media
In what type of media do basic drugs ionize?
Acidic
What factors can enhance the absorption process?
Rapid drug dissolution, high lipid solubility, large surface area, high blood flow at the site of administration
What are the advantages of IV administration?
Rapid onset
Precise control over the amount of drug entering the blood
Suitability for use with large volumes of fluid
Suitability for irritant drugs
What are the disadvantages of IV administration?
High cost
Difficulty
Inconvenience
Danger related to irreversibility
Potential for fluid overload, infection, and embolism
What are the advantages of IM and SubQ administration?
Suitability for insoluble drugs
Suitability for depot preparations
What are the disadvantages of IM and SubQ administration?
Inconvenience
Potential for discomfort
What are the advantages of oral administration?
Ease
Convenience
Low cost
Safety
What are the disadvantages of oral administration?
High variability
Possible inactivation by stomach acid, liver enzymes, and digestive enzymes
Which oral formulations are made to release in the small intestine?
Enteric-coated
These oral formulations are designed to release their contents slowly in order to increase the time between doses. What are they?
Sustained-release oral formulations
Define drug distribution.
Movement of drugs from the blood to the interstitial space of tissues and then into cells
Define blood-brain barrier.
The presence of tight junctions between the cells that compose capillary walls in the CNS
What substance do drugs typically bind to in the vascular system?
Plasma albumin
Where do most drugs metabolize?
Liver
What system of enzymes catalyze the metabolism of drugs in the liver?
Cytochrome P450
What is important when metabolizing drugs in the liver?
Converting lipid-soluble drugs to more hydrophilic forms to ease the process of their excretion
What are some consequences of drug metabolism?
Conversion to less active forms
Conversion to more active forms
Conversion of prodrugs to active forms
Conversion of drugs to more/less toxic forms
Define substrates.
Drugs that are metabolized by the P450 enzyme which can act as an inducer or inhibitor
How are plasma levels influenced by drug metabolism?
Plasma levels fall as drug metabolism increases
What is the first pass effect?
Some oral drugs are inactivated as they pass through the liver after being absorbed
What is enterohepatic recirculation?
A detoxification process in the liver where a drug travels through fluids to the duodenum and back to the liver as free drugs are released
What are the three steps of renal drug excretion?
- Glomerular filtration
- Passive tubular reabsorption
- Active tubular secretion
Why are lipid-soluble drugs less likely to be excreted by the kidneys?
Undergo an extensive reabsorption process into the blood where the liver works to convert them into more polar forms
Define minimum effective concentration.
The lowest amount for which therapeutic effects will occur
What is the half-life of a drug?
The time required for a certain amount of a drug in the body to decline by 50%
About how many half-lives are needed to reach plateau?
Four
What are some ways to reduce fluctuations in plasma drug levels?
- Giving smaller doses at shorter intervals
- Using a continuous infusion
- Using a depot preparation
How can plateau be reached quickly with a drug that has a long half-life?
Using a loading dose
In about how many half-lives will a drug leave the body after administration has been discontinued?
Four
Pharmacodynamics
The study of the biochemical and physiologic effects of drugs and the molecular mechanisms by which those effects are produced
