Exam 1 Flashcards
Pharmacodynamics
The study of the effects of drugs on the body
Beneficence
the duty to protect research subjects from harm. It involves assessing potential risks and possible benefits and ensuring the benefits are greater than the risk.
Risk-Benefit Ratio
absorption
the movement of the drug into the bloodstream after administration
excipients
Fillers and inert substances—such as simple syrup, vegetable gums, aromatic powder, honey, and various elixirs
used in drug preparation to allow the drug to take on a particular size and shape and to enhance drug dissolution
Pharmacokinetics
The process of drug movement throughout the body that is necessary to achieve drug action
Pharmacogenetics
The study of genetic factors that influence an individual’s response to a specific drug
6 Rights of Medication Safety
- Right patient
- Right drug
- Right dose
- Right route
- Right time
- Right documentation
Chemical Name
Describes the chemical structure of the drug
› N-aceTYL-p-aminopheno
Generic Name
Official, nonproprietary name
Brand (Trade) Name
Proprietary name
Generic Drugs
› Must be approved by the FDA
› Same active ingredients as brand-name drug
› Usually less expensive
› May contain products that aid in providing the shape of the tablets, control the timing of release in the body
› Health care provider must state on prescription whether a generic drug can be substituted for the brand name drug
Over-the -Counter (OTC) Drugs
Drugs that have been found safe and appropriate for use without the direct supervision of a health care provider
› Important for the nurse to be aware of their clients use of OTC drugs
Enteric-coated (EC) drugs
resist disintegration in the gastric acid of the stomach
should not be crushed because crushing alters the place and time of absorption of the drug
ext/sustained-release (beaded) capsules
should not be crushed
Bioavailability
the percentage of administered drug available for activity orally administered drugs, bioavailability is affected by absorption and first-pass metabolism;
IV = 100%, PO = <100%
Factors that alter bioavailability
(1) drug form, such as tablet, capsule, sustained-release beads, liquid, transdermal patch, suppository, or inhalation
(2) route of administration (e.g., enteral, topical, or parenteral)
(3) gastric mucosa and motility;
(4) administration with food and other drugs; and
(5) changes in liver metabolism caused by liver dysfunction or inadequate hepatic blood flow
Distribution
the movement of the drug from the circulation to body tissues
protein binding
The portion of the drug bound to protein is inactive because it is not available to interact with tissue receptors and therefore is unable to exert a pharmacologic effect
Free drugs
are able to exit blood vessels and reach their site of action, causing a pharmacologic response;
primarily relevant when considering protein-bound drugs, but they can be a factor for any drug that binds to plasma proteins
Metabolism (biotransformation)
process by which the body chemically changes drugs into a form that can be excreted
primary site of metabolism
liver
half-life
time it takes for the amount of drug in the body to be reduced by half
Loading Dose
a large initial dose, known as a loading dose, that is significantly higher than maintenance dosing, therapeutic effects can be obtained while a steady state is reached
excretion
elimination of drugs from the body, is through the kidneys
creatinine and blood urea nitrogen (BUN).
Creatinine = a metabolic by-product of muscle that is excreted by the kidneys;
BUN = is the metabolic breakdown product of protein metabolism.
will be high if kidneys are failing + creatinine clearance (assumed to be low)
decreased kidney function = longer drug halflife and increased drug exposure/toxicity
CR = (creatinine clearance) used to estimate the GFR, which measures how well the kidneys are filtering waste products
informed consent
clients have the right to be informed and participation is voluntary
autonomy
right to self determination
Justice
equability or equal selection of research participants
dose-response relationship
the body’s physiologic response to changes in drug concentration at the site of action.
Potency
a measure of a drug’s strength / amount required to produce a specific effect. Potency does not directly refer to the drug concentration but instead compares the concentration of one drug to another
A drug with high potency requires a lower dose or concentration to produce the same effect compared to a drug with lower potency.
maximal efficacy
the maximum effect or response that a drug can produce, representing the upper limit of its pharmacological effect; regardless of the dose or concentration. It is a characteristic of the drug itself.
(different from peak concentration)
therapeutic index (TI)
describes the relationship between the therapeutic dose of a drug (ED) and the toxic dose of a drug (TD)
Onset
time it takes for a drug to reach the minimum effective concentration
peak
occurs when it reaches its highest concentration in the blood.
nonspecific / nonselective drug
Drugs that affect multiple receptor sites
Mechanisms of drug action
(1) stimulation, (2) depression, (3) irritation, (4) replacement, (5) cytotoxic action, (6) antimicrobial action, and (7) modification of immune status.
tachyphylaxis
an acute, rapid decrease in response to a drug, not indicative of time; it may occur after the first dose or after several doses