Chapter 2 Flashcards
What is a drug?
Any chemical that effects the physiologic processes of a living organism
What is pharmacology?
Study or science of drugs
What are the 5 pharmacologic principles?
Pharmaceutics Pharmacokinetics Pharmacodynamics Pharmacotherapeutics Pharmacognosy
What are the 3 drug names?
Chemical
Generic (nonproprietary name)
Trade (proprietary name)
What is the Chemical name?
Drug’s chemical composition and molecular structure
What is the Generic name?
Name given by the United States Adopted Name Council
What is the Trade name?
The drug has a registered trademark; use of the name is restricted by the drug’s patent owner (usually the manufacture)
AKA Brand name
What is Pharmaceutic?
The study of how various drug forms influence pharmacokinetic and pharmacodynamic activities.
(designates when ingested)
What is Pharmacokinetics?
The study of what the body does to the drug
What does the body do to a drug?
Absorption Distribution Metabolism Excretion (ADME)
What is Pharmacognosy?
The study of natural (plant and animal) drug source
What is Pharmacodynamics?
The study of what the drug does to the body
What does the drug do to the body?
The mechanism of drug actions in living tissues
What are the fastest absorbed oral preparations?
Liquids, elixirs, and syrups
What are the slowest absorbed oral preparations?
Enteric-coated tablets
What is Pharmacotherapeutics?
The use of drugs and the clinical indications for drugs to prevent and treat diseases.
What is the Pharmacokinetics absorption?
The rate at which a drug leaves its site of administration and the extent to which absorption occurs.
Bioavailability
Bioequivalency
What is Bioavailability?
The % of administered dose of unchanged drug that reaches systemic circulation.
What is Bioequivalency?
2 different formulations may have comparable bioavailability.
What are the factors the affect absorption?
Food and fluids administered with the drug
dosage formulation
status of the absorptive surface
rate of blood flow to the small intestine
acidity of the stomach
status of the GI tract
Absorption characteristics vary according to the dose ________ and _______
form and route
A drugs route of administration affects the ____ and _____ of absorption of that drug
rate and extent
What are the 3 routes of administration of a drug?
Enteral (GI tract)
Parenteral (injections)
Topical (dermal, inhalers)
What is an enteral route?
The drug is absorbed into the systemic circulation through the oral or gastric mucosa or the small intestine
What are the enteral routes?
Oral
Sublingual - Fast
Buccal - Fast
Rectal
What is the first-pass effect?
The metabolism of a drug and its passage from the liver into the circulation
A drug given via the oral route may be extensively metabolized by the liver before reaching the systemic circulation. This is called?
First-pass effect
The same drug given IV will bypass the liver, prevent ____________ from taking place and more drug reaches the circulation.
First-pass effect
What are the parenteral routes?
Intravenous (fast delivery into the blood circulation) Intramuscular Subcutaneous Intradermal Intraarterial Intrathecal Intraarticular Transdermal also can be consider parenteral
What are the topical routes?
Skin Eyes Ears Nose Lungs Rectum Vagina
What is distribution?
The transport of a drug in the body by the bloodstream to its site of action.
What are the distribution?
Protein-binding
Water soluble vs fat soluble
Blood-brain barrier
Area of rapid distribution: heart, liver, kidneys, brain
Area of slow distribution: muscle, skin, fat
Biologic transformation of a drug into:
An inactive metabolite
A more soluble compound
A more potent metabolite
Factors the decrease metabolism
Cardiovascular dysfuntion Renal insufficiency Starvation Obstructive jaundice Slow acetylator Erythromycin or ketoconazole drug therapy
Factors that increase metabolism
Fast acetylator
Barbiturate therapy (enzyme inducer)
Rifampin therapy
Delaying drug metabolism causes:
Accumulation of drug
Prolonged action of the drug - drug toxicity
Stimulation drug metabolism causes:
Diminished pharmacologic effects
What is excretion?
The elimination of drugs from the body
What are the excretion?
Kidneys (main)
Liver
Bowel - biliary excretion & enterophepatic recirculation
What is a half-life?
The time it takes for one half of the original amount of the drug to be removed from the body
Most drugs are considered to be effectively removed after about _____ half lives
five
What is steady state?
The amount of drug removed via elimination equal to the amount of drug absorbed
What is onset?
The time it takes for the drug to elicit a therapeutic response
What is peak?
The time it takes for the drug to reach its maximum therapeutic response
What is duration?
The time a drug concentration is sufficient to elicit a therapeutic response.
During peak level the blood is at its _______
highest level
During trough level (nadir) the blood is at its ________
lowest level
What is an agonist?
A chemical that binds to some receptor of a cell and triggers a response by that cell.
What is a partial agonist?
Drugs that bind to and activate a given receptor, but have only partial efficacy at the receptor relative to a full agonist.
What is an antiagonist?
A type of receptor ligand or drug that does not provoke a biological response itself upon binding to a receptor, but blocks or dampens agonist-mediated responses.
What are the pharmacodynamics mechanism of action (MOA)
Receptor interaction
Enzyme interaction
Nonselective interaction
Types do therapies in pharmacotherapeutics:
Acute therapy - short term
Maintenance therapy - chronically
Supplemental/replacement therapy - insulin, iron
Palliative therapy - comfort care
Supportive therapy - fluids/electrolytes
Prophylactic therapy - prevent illness
Empiric therapy - medication due to signs & symptoms
What is contraindications?
Any characteristic of the patient, especially a disease state, that makes the use of a given medication dangerous for the patient.
Therapeutic index
Ratio o a drug’s toxic level to the level that provides therapeutic benefits
Tolerance
Decreasing response to repeated drug doses
Dependence
Physiologic or psychological need for a drug
What is physiologic?
Physical need for the drug
What is psychological?
Addiction
Interactions may occur with other _____ or ______
drugs or food
A drug interaction is the alteration of a drug’s action by:
Other prescribed drugs
OCT medications
Herbal therapies
Drug interactions:
Additive Synergistic Potentiation Antagonistic Incompatibility
Pharmacognosy 4 main sources for drugs:
Plants
Animals
Minerals
Laboratory synthesis
What is the study of the physiochemical properties of drugs and how they influence the body called?
Pharmacodynamics
Pharmacokinetics involves the study of
distribution rates among various body compartments
How can drugs exert their action on the body?
By interacting with receptors
By inhibiting the action of a specific enzyme
By altering metabolic chemical processes
What is an alternate name for biotransformation of a drug?
Metabolism
A drug given by which route is altered by the first-pass effect?
Oral
Drug half-life is defined as the amount of time required for 50% of a drug to
Be eliminated by the body
Which action will increase the absorption of a medication administered intramuscularly?
Massaging the site after injection
Highly protein-bound drugs
increase the risk of drug-drug interactions.
To achieve the most rapid onset of action, by which route will the health care provider administer the medication?
Intravenously
Patients with renal failure would most likely have problems with drug
excretion
What is the ratio between a drug’s therapeutic effects and toxic effects called?
Therapeutic index
Which factors will affect the absorption of orally administered medications?
Presence of food in the stomach
pH of the stomach
Form of drug preparation
Time of day
When a patient asks the nurse why a lower dose of intravenous pain medication is being given than the previous oral dose, what knowledge will the nurse draw on for her response?
Medications given intravenously are not affected by the first-pass effect.
