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Pharmacology: Exam 1 -
Inroduction to Pharmacology
145
Nursing
Graduate
12/15/2009

Additional Nursing Flashcards

 


 

Cards

Term
Pharmacokinetics
Definition

How a drug gets into the body and is distributed

(Absorption, Distribution, Metabolism, Excretion)

Term
Pharmacodynamics
Definition

How a drug affects the body processes

(Including therapeutic and undesirable effects)

Term
Patient Specific Factors that may produce what results when taking the drug? (2)
Definition

1. Alter the drugs ability to produce its therapeutic effects or increase its side effects

2. Might cause an idiosyncratic reaction, like a drug allergy, or other effects particular to the patient

Term
Idiosyncratic Reactions
Definition
Drug Allergy
Term
What is the first step to prescribing a new drug to the patient?
Definition
Evaluate the patient
Term
Evalaute the following patient characteristics that could impinge on drug administration or activity:
Definition

1. Pregnancy

2. Age

3. Other drugs the patient is taking

4.Health status, inclduing cognitive function

5. Lifestyle, diets and habits

6. Environment

7. Cultural/Ethnicity

8. Idiosyncratic reactions (allergies)

9. Characteristics that would affect the patients ability to respond to a drug or produce a therapeutice effect

Term

Patient Evaluation:

Lifestyle, diet and habits

Definition

* Use of OTC medications, herbals, etc

* Substance Abuse

* Health insurance/prescription drug coverage

* Support system: Family, significant other

Term

Patient Evaluation:

Environment

Definition

* Occupational or other eposure to toxic substances

* Setting in which the drug will be administered

Term

Patient Evaluation:

Culture/Ethnicity

Definition

* Religious, social and ethnic background

* Genetic Traits

Term
Where to get patient information from?
Definition

* Past Medical History

* Physical

* Family members, friends, etc

Term

The Nursing Process in Pharmacology:

Assessment

Definition
Incdlue patient factors and drug information
Term

The Nursing Process in Pharmacology:

Diagnosis

Definition
Identify deficits
Term

The Nursing Process in Pharmacology:

Planning

Definition

* Maximize therapeutic effects and minimize adverse effects

* Include the patient & family in the planning

Term

The Nursing Process in Pharmacology:

Intervention

Definition

* 5 Rights of Drug Administration

Right Time

Right Route

Right Patient ID

Right Medication

Right Drug

Right Documentation

 

* Patient education must be a part of the intervention

Term

The Nursing Process in Pharmacology:

Evaluation

Definition

* Is the patient taking the drug as prescribed?

* Is the drug producing the effect it is supposed to?

* Are the adverse effects acceptable?

* Should the dose be increased or decreased, or a different drug substituted?

* Does the patient need to continue this therapy?

Term

The Nursing Process in Pharmacology:

Explain the Whole Process

Definition

 

1.Assessment:  Includes patient factors and drug information
2.Diagnosis:  Identify deficits
3.Planning:
Maximize therapeutic effects, minimize adverse effects
Include the patient/family in the planning.

 

4.  Intervention:

The 5 rights of drug administration:  right route, right patient, right drug, right dose, right time
Patient education must be a part of the intervention.

5.  Evaluation:

Is the patient taking the drug as prescribed?
Is the drug producing the effect it is supposed to?
Are the adverse effects acceptable?
Should the dose be increased or decreased, or a different drug substituted?
Does the patient need to continue this therapy?
Term

Every drug has atleast _##_ names.

What are they?

Definition

1. Chemical Name

2. Generic Name

3. Trade Name

Term
Chemical Name
Definition

*Not used by health care providers*

 

* Describes the chemical structure of the drug

* This is usually irrelevant to healthcare practitioners and patients because we want to know what the drug does, not its structure

* Drugs with different chemical structures can do the same thing

Term
Generic Name
Definition

Used no matter where or what the setting, prep (IV, Pills), International name (in a differnt country , the drug will have a different trade name, but the same generic name

* Assigned to the drug when it is first given to humans

* The drug is always known by this generic name

* The generic name is printed on a bottle or in advertisements in parentheses

* Is not capitalized

* Sometimes hard to say

Term

Trade Name

 

Definition

* Advertised name

* Name is given to the drug by the drug company that makets it

If more than one drug company markets a particular drug, it will have a different name for each company

* Name is capitalized

Term
Why use generic name over trade name?
Definition

1. Avoids confusion (generic names are universal)

 

* In clinical practice, always look at the generic name to avoid giving the same drug twice

 

 

Term

In the drugstore, you see pill bottles iwth the following names:

1. Advil (ibuprofen) 200 mg

2. Ibuprofen, 200 mg

3. Motrin (ibuprofen) 200 mg

4. Nuprin (ibuprofen) 200 mg

 

Which of the following is true?

A. They all contain the same drug.

B. People with muscle pain should only take Motrin

C. Motrin is the generic name

D. Nuprin is only for headaches

Definition
A. They all contain the same drug.
Term
What are 3 ways to classify drugs?
Definition

1. According to their use (ex: Antihypertensive)

Confusing because many drugs have more than one use

 

2. According to their mechanism of action (Preferred)

Most useful classification since it explains all the actions of the drug

 

3. According to their chemical structure

Limited usefulness for healthcare providers; irrelevant

 

Term
Classify by Use vs. Classify by Mechanism of Action
Definition

Ex: Calcium channel blockers block calcium channels in smooth and cardiac muscles; When blocking smooth muscle, they reduce blood pressure; when blocking cardiac muscles they slow conduction

 

USE: We would have to memorize 2 uses

 

MECHANISM OF ACTION: Learn about the drug once, and apply the knowledge to different uses

Term
Advantages of classifying by MECHANISM OF ACTION
Definition

* Allows us to know what a new drug will do (since we can put it into a class whose mechanism of action we know)

 

(Ex: If a new calcium channel blocker was introduced, we would already know what it does and possible side effects)

Term
Drug information changes ___________.
Definition

DAILY

 

1. Introduction of new drugs

2. New administation routes for older drugs

3. New adverse effects and/or warning may be issued

4. Drugs taken off the market

Term
Sources of drug information
Definition

1. Pharmacology book (Not a good way for updates; website stays current)

2. Physicians Desk Reference (PDR) for prescription and OTC drugs - comes with the drugs to protect the drug companies

3. Formularies

4. Drug compendiums - useful for dosage, not mechanism of action or class

5. Reputable websites (Mayoclinic, associations (heart, diabetic), advocacy websites

Term
What is the purpose of the Physicians Desk Reference (PDR) for prescription and OTC drugs?
Definition

-PDR's come with drugs

-Main purpose is to protect the drug company from lawsuits

-Black box warnings (adverse effects)

-Only information given in the PDR is what the drug was approved for by the FDA

Term
Who approvesa and allows new drugs to be marketed?
Definition

Food and Drug Administration (FDA)

 

* Dietary supplements and herbals do not go through the same approval process as medical drugs

Term
Drug companies must show evidence that a drug has ___________.
Definition

Efficacy

 

* Drug company must have an indication (disease or condition) that the drug is supposed to make better)

Efficacy = power to produce a desired effect

Term

A drug is approved by the FDA for _##_ uses at a time.

 

A drug could be effective for _##_ uses.

Definition

ONE - A drug can be approved for one indication at a time.

 

A drug might be good for more than one use, but the drug company has to choose which use they want to seek approval for at a time.

 

*Drug companies choose the use that can be marketed to the largest amount of people.

Term
Explain the term "off-label" use.
Definition

Once a drug is approved for marketing, it can be prescribed for anything by anyone authorized to prescribe drugs (off-label use)

 

There is nothing illegal about giving a drug for an off-label use; however, if an adverse effect occurred, the provider could be sued for malpractice

 

There is usually literature that supports the off-label use

Term
Could a provider be sued for giving a drug for an off-label use?
Definition
No - only if it produces an adverse effect, then the provider could be sued
Term
After the drug is proved to show efficacy, it must prove to be ______.
Definition
Safe
Term
Is there a such thing as a completely safe drug?
Definition

NO

 

Danger presented by the drug has to be balanced against the benefits

Term
If the benefits of a drug are great, will we (& FDA) compromise on the drugs safety?
Definition

YES

 

Example: Chemothrapy is a life=saving drug that will cure cancer, but has severe adverse effects

 

Example: Cough Medicines for young children are dangerous and they do not work that well for children; there are more dangers then benefits for cough medicines for children

Term

Give an example of a drug with high benefits but low safety.

Give an example of a drug with low benefits and low safety.

Definition

Example: Chemothrapy is a life-saving drug that will cure cancer, but has severe adverse effects

 

Example: Cough Medicines for young children are dangerous and they do not work that well for children; there are more dangers then benefits for cough medicines for children

Term
Safety for medications given over a long time.
Definition
A drug taken over a long period of time, such as an anti-hypertensive drug, should be safer than a drug taken for a short period of time or only once
Term
Why should OTC medications be safer then prescription drugs?
Definition
OTC medications should be safer than prescribed drug because we expect the prescriber of a prescritpion drug to monitor the patient
Term
How can a drug company receive permission from the FDA to administer the drug to humans in clinical trials?
Definition
Drug company needs to have pre-clinical data that supports safety and efficacy
Term
Safety Studies in Animals:
Before being able to test a new drug on humans, the drug company will run clinical trials on ______________ with the understanding that it is meant for evenutal use in _________.
Definition

Before being able to test a new drug on humans, the drug company will run clinical trials on animals with the understanding that it is meant for evenutal use in humans.

 

Term
Safety Studies in Animals:
Initial pre-clinical animal studies are done on ______ & _____ because _______.
Definition

Initial pre-clinical animal studies are done on mice and rats because they are cheap and have a short life span

 

For more complex drugs, such as drugs that make you vomit (ntiemetic drug), cats, dogs or ferrets will be used

Term
Safety Studies in Animals:
The purposes of animal studies are to ...
Definition

1. Provide evidence of safety and efficacy in animals

2. To determine an estimated effective does that can be upscaled for humans

Term

Safety Studies in Animals:

Increasing doses of the drug are used in animal studies to determine __________.

Definition
Adverse effects
Term

Safety Studies in Animals:

Adverse effects are determined in animals by __________ in clinical studies.

Definition
Adverse effects are determined in animals by increasing doeses of the drug in clinical studies.
Term

Safety Studies in Animals:

Animal blood, urine and organs provide data about how the drug is ________________________.

Definition
Animal blood, urine and organs provide data about how the drug is distributed in thh body and how it is eliminated.
Term
Safety Studies in Animals:
Short and long-term administration provide _____ data of different time courses.
Definition
Safety
Term
Safety Studies in Animals:
Pregnant animals are used to study .....
Definition
Teratogenicity (fetal malformation)
Term
Safety Studies in Animals:
Animals on long-term administration are monitored for number of things including ___________.
Definition
The Development of Cancers
Term
What is an Investigaational New Drug (IND) application?
Definition

Drug company presents all pre-clinical data to the FDA (safety, efficacy and animal studies) in an IND application to request the FDA's approval to enter clinical trials on humans.

 

IND also includes a plan of how human testing will be conducted

Term
Once the IND application has been submitted and approved by the FDA, what happens during the next phase (Phase I)?
Definition

Phase I:

 

** Conduct human testing to determine the dose to be used during future studies **

 

 

Term

Phase I Testing:

What type of participants are used?

What is the purpose of Phase 1? How the purpose accomplished? 

Definition

Purpose of Phase I Testing: To determine the dosage of the drug for future studies

 

* Normal, healthy people are used, with the exception for drugs that treat cancer and AIDS

 

* Started with a low dose and increase the dose until participants cannot tolerate it

-Maximum tolerated dose: Dose is increased in a stepwise fashion until intolerable adverse events occur

* Measurements of blood and urine are taken to determine how the drug is distributed and eliminated

 

* Most Phase I trials have 10-50 subjects

Term
What is Phase II of the drug approval process?
Definition

Participants: Patients with the condition or disease are treated

 

Dosages: Are adjusted based on response

 

Blood and urine are taken to determine drug distribution and elimination

 

Purpose: Learn about drug distribution and elimination and an effective dosage range to treat the condition

 

*Less then 50 people

Term
What is the purpose of each phase of the new drug approval process?
Definition

Phase I: Tolerable Dosages

Phase II: Drug distribution and elmination; dosage range

Phase III: Determine safety and efficacy

Phase IV: Continue surveillance and reported side-effects

Term

Explain Phase III of the process to approve a new drug.

 

Who participates in the trial? What is the phase demonstrating? What is the drug compared with in this phase?

Definition

* Large clinical trial with 100's of subjects who have the condition

* Demostrates safety and efficacy of the drug when treating the indication

* The drug must be compared with something: Placebo, or if not ethical, with a standard treatment for that condition

Term

Phase III:

In Phase III the new drug must be compared with ______ or _______.

Definition
In Phase III the new drug must be compared with a placebo or standard of treatment (if placebo is not ethical)
Term

Phase III:

The large clinical trial of hundreds of subjects who have the condition must demonstrate _________ & ____________ of the drug in treating that __________.

Definition

The large clinical trial of hundreds of subjects who have the condition must demonstrate safety & efficacy of the drug in treating that indication.

 

 

Term

Phase III:

Phase III trial subjects must meet inclusion criteria and exclusion criteria. What is inclusion criteria? What is exclusion criteria?

Definition

Inclusion Criteria: Make sure the subjects actually have the disease in queastion and that they are likely to be helped by the therapy.

 

Exclusion Criteria: Exclude people likely to be harmed by the therapy (ex: Pregnancy) or people wtih serious comorbidities

**This explains why there is rarely any data on children or pregnant women**

Term

Phase III:

What type of study is used during Phase III of an FDA drug approval?

Definition

Double-Blinded study with randomized subjects receiving either the investigation drug or the comparaor (placebo or standard treatment)

 

Double Blinded Study = neither the subject nor the person administering the drug knows whether it is the expeimental drug or the comparator)

Term

Phase III:

How many times must a drug company complete a Phase III trial before a drug is approved?

Definition

Normally, once; however, the FDA can mandate more Phase III trials if they think its necessary

 

* Also, if the drug company wants to market the drug for more than one indication, there woudl be a phase III trial for each indication

Term
If a drug company wants to market a 2nd indication for the same drug, which phases must be repeated for the new indication?
Definition
Phase III
Term

Phase III:

Characteristics of Phase III Trials

Definition

* Hundreds to thousands of subjects

* Subjects have condition

* Comparator involved (Placebo or standard treatment)

* Double Blinded Study

* Last several months to years

* Subjects are monitored very closely for progression of their disease or for adverse effects

Term
Who is able to stop clinical testing on an Investigational New Drug (IND)?
Definition
FDA or drug company can stop the whole process at any time
Term
What happens after an Investigation New Drug (IND) has successfully completed Phase III?
Definition

Company submits a New Drug Application (NDA)

 

Data from Phase 1, 2 & 3 are presented

 

A draft of the prescribing information is proposed (Material to be publisehd in the PDR)

 

Drug company and FDA negotiate the prescribing information, warnings of adverse effects, etc.

Term
What is a New Drug Application (NDA)?
Definition

Drug company submits a New Drug Application (NDA) at the end of Phase III with data from Phase 1, 2 & 3 and a proposed draft of the prescribing information (PDR). FDA and Drug company then negotiates prescribing information and warnings.

 

Term
Once a drug company gets permission to market a new drug for the indication used in clinical trials, what is negative outcome that could occur and why?
Definition

Throughout phases 1, 2 & 3, the drug had been given to fewer then 1,000 people; when it is market, it will be givin to millions;

Therefore, several new adverse effects that were not evident during clinical trials, may occur from the new drug

Term

What is Phase IV of the new drug approval process?

(Continuous Surveillance)

Definition

Continuous Surveillance

Not a formal study

Post-Marketing Study that relies on spontaneous reports from practitioners or patients about adverse events

*May take years for some adverse effects to be attributed/linked to the drug

 

Since there is no control group, it is very hard to show taht a particular adverse event is due to the drug and is not just a coincidence

 

Term
Why is it hard to directly relate an adverse effect to the drug?
Definition

No control group: It is hard to show that adverse effects is due to the drug and not a coincidence

 

Also, all post marketing surveillance relies on spontaneous reports from practitioners or patients - Not all adverse effects may be reported

Term

In which stage of drug development are researchers concerned with the drug's maximum tolerated dose?

A. Phase I

B. Phase II

C. Phase III

D. Phase IV

Definition
A. Phase I
Term

Drug Pricing:

Describe the Drug Pricing Process of New Drugs

Definition

1. 1st Protected by a patent issued to the drug company

2. It is marketed under the company's brand name, typically priced really high (to recoup costs of developing the drug)

3. After the patent expires, anyone can make the drug (as long as it satisfies FDA approval) - Generic variations of the drug are market for very cheap

Term

Drug Pricing:

When a drug is first approved, it is protected by a _____.

Definition
Patent issued to the drug company who developed the drug.
Term

Drug Pricing:

Company will market the drug under its trade name, with the generic name in lower case letters, for (High or Low)__ prices to ____________.

 

 

Definition

High Prices

 

To Recoup the costs of developing the drug

Term

Drug Pricing:

When can generic brands of the drug be marketed?

Definition
After the patent expires
Term

Drug Pricing:

Generic brands of the drug can be marketed after the developing drug companies patent expires. What do some drug companies do to extend their patent?

Definition
The Original drug company will come out with an improvement to extend their patent - ex: Create concentrated medication, so less doses are needed
Term

Drug Pricing:

Generic brands of the drug can be marketed after the developing drug companies patent expires. What are FDA standards the generic drug must comply to? What are differences between the generic drug and the brand/trade drug?

Definition

There is NO difference between the generic and trade drug because FDA regulations has standards that force the company marketing the generic brand to make sure the generic drug is the same as the trade name drug in terms of its activity and purity

 

* Generic drug is much cheaper then the trade name drug

Term
What are controlled substances?
Definition
Drugs that have the potential for abuse
Term
Controlled Substances are regulated by the _____________________.
Definition

Drug Enforcement Administration (DEA)

 

*Not the FDA*

Term
Controlled substances are regulated by prescribers who have a ____________________ which regulate the number of controlled substance prescriptions being prescribed.
Definition
DEA Number
Term
Prescribers of controlled substances and DEA numbers are regulated by the _______.
Definition
State
Term
Nurses, pharmacies and hospitals must also comply with the ____________________ to handle controlled substances.
Definition
DEA Regulations
Term
Drug Enforcement Act (DEA) Regulates ....
Definition
The quantities of substances and who receives them
Term

Controlled Substances:

Drug Schedules

 

Explain the differences between schedule 1-5 controlled substances

Definition

 

Schedule

Abuse Potential

Dependence Liability

Examples

Rules

I

High

Severe

Heroin,  LSD

No acceptable use

Research only

II

High

Severe

Amphetamines, some opioids

Triplicate prescriptions, no refills

III

Moderate

Moderate

Some opioids, some stimulants, anabolic steroids

Written or telephone prescription every 6 mos, refills allowed

IV

Low

Limited

Tranquilizers, weak opioids

Same as schedule III

V

Limited

Lowest

Antidiarrheals, drugs that contain small amounts of opioid in a medication mixture

Many OTC

Term

Controlled Substances:

Drug Schedules

 

Explain the differences between schedule 1-5 controlled substances

Definition

Schedule 1: High Abuse, No acceptable use, research only (ex: Heroin, LSD)

Schedule II: High Abuse, triplicate prescriptions, no refills (ex: Amphetamines, Opiods)

Schedule III: Moderate Abuse, Written or telephone prescription every 6 months refills allowed (Stimulants, Anabolic steroids)

Schedule IV: Low Abuse, Written or telephone presciription every 6 months refills allowed (Tranquilizers, weak opoids)

Schedule V: Limited Abuse, Many OTC, (Ex: Antidiarheals)

Term
What is pharmacology?
Definition
The study of drugs and their interactions with living systems.
Term
What is a drug?
Definition
A drug is any chemical that can affect a living process.
Term
What is pharmacodynamics?
Definition
The study of the interaction between a drug and its receptor to produce an effect (in the body)
Term

What is pharmacokinetics?

(2 Functions)

Definition

1. Study of how a drug gets to its receptor in the body (This is broken down into absorption and distribution)

 

2. Study of how a drug leaves the body changed or excreted by the body processes (Elimination)

Term

Explain the Receptor Theory

(Erilich, 1916)

Definition

* Drugs produce specific affects because they interact with specific molecules in teh body

* Drugs alter the rate of the natural function of the macromolecule (Drugs do not create new functions; they increase or decrease the rate of the curent function)

Term

Erilich, 1916: Receptor Theory

 

Drugs produce effects because they interact with _____________ in the body.

Definition
Specific Molecules
Term

Erilich, 1916: Receptor Theory

 

Drugs alter the _______ of the natural function of the macromolecule.

Definition
Rate
Term
What type of physiologically macromolecules serve as drug receptors?
Definition

Any molecule inthe body can serve as a drug receptor

 

Enzymes, neurotransmitter receptors, ion channels, transport proteins

Term

Definition of a receptor

(by pharmacologists)

Definition

A receptor is a macromolecule with endogenous ligands.

 

A ligand is a chemical that binds to a receptor and activates it, causing some change to occur

Term
What is a ligand?
Definition

A ligand is a chemical that binds to a receptor and activates it, causing some change to occur

 

A receptor is a macromolecule with endogenous ligands.

 

Term
4 Classes of Macromolecules that define receptors
Definition

1. Membrane-Bound enzymes with activating ligands

2. Ligand-gated ion channels

3. G-Protein coupled neurotransmitter receptors

4. Transcription factors with activating ligands

Term

Examples of Endogenous Ligands:

Neurotransmitters bind to ________________.

Definition
Neurotransmitter receptors
Term

Examples of Endogenous Ligands

Steroids bind to their respective receptors which are ____________________ factors.

Definition
transcription
Term
4 Classical Receptors with Endogenous Ligands
Definition
[image]
Term

Other macromolecules drugs can bind to in order to initiate change in function

(These are not classical receptors)

Definition

Enzymes

Ribosomes

Tubulin

DNA

RNA

Transporters (Na- or K+ Pumps)

Term
If a drug only binds to one receptor type, then .....
Definition
the drug will cause a very specific effect
Term
If a drug binds to more then one receptor type ....
Definition
the drug will cause unwanted or additional effects due to activity at all receptors
Term

Most drugs bind to more than one receptor type and ahve effects due to activity at all those receptors.

 

Example: Explain how this is true with Beta Blockers

Definition
Beta Blocker drugs bind to both Beta (B) 1 and B2 receptors. (Beta 1 receptors are located in the heart, because here is 1 heart; Beta 2 receptors are located in the lungs because there are 2 lungs). Beta blocker drugs can cause bronchiolar constriction at B2 receptors in the bronchi (lungs), as well as slowing of the heart rate at B1 recetpors at the SA node in the heart.
Term
Drug activity at more the one receptory could be _____ or _____.
Definition

Good or Bad.

 

Good: A drug that blocks both Beta and Alpha receptors are good anti-hypertensive agents

 

Bad: B Blocker might also block serotonin receptors and cause bad dreams

Term
Explain the drug response curve.
Definition

1. Pre-Threshold: Few receptors in the body are bound by a drug. It is such a small response, it is not detectable in a whole animal or person.

 

2. Threshold is Reached: Response can be detected. More drug produces a bigger effect because more receptors are bound.

 

3. Plateau: All receptors are bound by a drug. No matter how much more drug is received, no additional response is produced.

Term
Drug Response Curve
Definition
[image]
Term

Drug Response Curve

Once the threshold is reached, will a response be detected?

Definition
Yes - More drug produces a bigger effect because more receptors are bound.
Term

Drug Response Curve

What occurs at the plateau of the drug response curve?

Definition
All receptors are bound by a drug and no matter how much more drug is geven, no additional response is produced.
Term

Drug Response Curve

Before the threshold is reached, can a response be detected?

Definition
No because only few receptors are bound
Term
What is potency?
Definition

The amount of drug needed to produce the same a desired result.

 

A more potent drug binds to the receptors more avidly, so that a high proportion of receptors are bound with the drug, even at low doses.

 

Less potent drug is not attracted to the recetpors to the same extent and it takes higher doses to produce the same degree of receptor occupancy

Term
What is more important, a more potent drug or a drug that has more efficacy?
Definition

Efficacy - we want the drug to work.

 

Some drugs will never create a desired response like others - Example: Morphine for pain will create a needed result for someone going through surgery, where tylenol would not even compare. In this situation, tylenol would have less efficacy and morphine would have more

Term
Explain the difference between Potency and Efficacy
Definition
[image]
Term

Modified Occupancy Theory

What are the 3 things the Modified Occupancy Theory takes into account that the Simple Occupancy Theory did not?

Definition

A drug binding to a particular receptory may:

 

1. Mimic the endogenous ligand's activity at that receptor

2. Produce a lesser effect than the endogenous ligand

3. Produce no effect

 

** A drug that produces no effect at the receptor will produce an effect in the body by preventing the bindg of the endogenous ligand.

Term

Modified Occupancy Theory

A drug that produces no effect at the recetpor will produce an effect in the body by .......

Definition
Preventing the binding of the endogenous ligand.
Term
What is intrinsic activity?
Definition
The ability of a drug to activate a particular receptor when bound to it.
Term
Endogenous Ligands have _________ intrinsic activity.
Definition

Full

 

A receptor is a macromolecule with endogenous ligands.

 

A ligand is a chemical that binds to a receptor and activates it, causing come change to occur

Term

Explain the types of agonists and how they are related to the endogenous ligand.

A. Full Agonist

B. Partial Agonist

C. Antagonists

Definition

Full Agonist: Full intrinsic activity (mimcs the endogenous ligands)

 

Partial Agonists: Less than full intrinsic activity (Less efficacious than full agonists)

 

Antagonists: No intrinisic activity; block the activity of the endogenous ligand by occupying the receptor

Term
What is a full agonist?
Definition
Full Agonist: Full intrinsic activity (mimcs the endogenous ligands)
Term
What is a partial agonist?
Definition
Partial Agonists: Less than full intrinsic activity (Less efficacious than full agonists)
Term
Antagonists
Definition
Antagonists: No intrinisic activity; block the activity of the endogenous ligand by occupying the receptor
Term
The effect of an antagonist depends on the concentration of the _________________ present.
Definition

Agonist (intrinsic ligand)

 

If there is no endogenous ligand, there was no effect anyway, so blocking it won't do anything

Term
Competitive Antagonists can be overcome by increasing the concentration of the ________.
Definition
Agonist
Term

Which of the following terms is defined as "the ability of a drug to activate a receptor upon binding"?

A. Affinity

B. Intrinsic Activity

C. Efficacy

D. Potency

Definition
B. Intrinsic Activity
Term
Explain Competitive vs. Noncompetitive Antagonism
Definition

1. A competitive antagonist binds reversibly to the receptor, causing the bound drug to be in equilibrium with the unbound drug

 

2. As a molecule unbinds from the receptor, its place will be taken by another molecule of the same drug or by a molecule of the endogenous ligand

 

3. If we want to overcome the effect of the 1st drug (antagonist), we could give a 2nd drug (agonist) in a high dose, increasing the chance that a vacant receptor will be occupied by the 2nd agonist drug in place of the 1st antagonist drug

 

4. At high enough concentrations of the agonists, we "win the competition", ensuring that vacant receptors will always bind to agonist.

Term
How do we overcome the effects of a competitive antagonist?
Definition
Give an agonist in higher doses to increase the chance that a vacant receptor will be occupied by the agonist instead of the antagonist.
Term

Receptor Sensitivity

What happens to receptors that are continually exposed to an agonist?

Definition
Their response may down regulate
Term
Receptor Sensitivity Down Regulation can be Rapid or Slow. Explain characteristics of both.
Definition

Rapid Downregulation: Tachyphylaxis (diminished response) or Desensitization

 

Slow/Permanent Downregulation: Tolerance or tachyphylaxis

Ex: Opiate drugs need to increase dose for the effect

Term
Downregulation is equal to
Definition
Tolerance
Term
Example of Downregulation or Tolerance in people who take opoid drugs for chronic pain.
Definition

People who take opioid drugs for chrnoic pain gradually have to increase teh dose because the dose they are taking becomes ineffect in relieving their pain (Opioid tolerance)

 

As a result, they may be taking doses that will cause a respiratory arrest in a drug-naive person. However, they are able to remain active and alert because they have tolerance to the drug.

Term
What factors result for loss of drug effect?
Definition

* Receptor downregulation

Anythign that speeds up elimination of the drug will result in lower drug levels and a less effect (pharmacokinetics)

Term
What is Receptor Upregulation?
Definition

When a person takes an antagonist for a long period of time, receptors may upregulate so there are more of them per cell

 

The antagonist still has an effect if its present in high concentrations

 

The problem comes when the person stops taking the antagonist; Since there are more receptors, the endogenous agonists will have a pronounced effect called supersensitivity

Term
Supersensitivity
Definition
When a person stops taking an antagonist that caused an upregulation of receptors, the endogenous agonists will have a pronounced effect; the effect is caused supersnesitivity
Term
Down regulation vs. Upregulation
Definition

Downregulation: Process by which a cell decreases the quantity of cellular components

 

Upregulation: Process by which a cell increases the quantity of cellular components

Term

True or False

 

Sudden discontinuation of a drug allows the endogenous agonist to have access to the receptors, is not dangerous.

Definition

False

 

It is very dangerous

 

Desensitization causes the endogenous agonist to produce a deficiency state (whatever natual fucntion that drug was affecting, they are not able to produce the same function)

 

Increased sensitization causes the endogenous agonist to produce greatly exaggerated effects

Term
What happens when an endogenous agonist is exposed to the receptors after prolonged agonist administration causing desensitization?
Definition
Deficiency State: Endogenous agonist will have little effect (whatever natural function that drug was affecting, they are not able to increase it)
Term
What happens when an endogenous agonist is exposed to the receptors after prolonged agonist administration causing increased sensitization?
Definition
The endogenousagonist may produce greatly exaggerated effects
Term
Drug responses varies between individuals. ________________ curves show us how a population responds to a drug.
Definition
Frequency Distribution
Term
Frequency Distribution Curve Explanation
Definition

1. Response is strictly defined. (Ex: 10% reduction in BP)

 

2. If a low dose is given, a few people will exhibit a response. These people are removed from the mix.

 

3. As the dose increases, more and more people will achieve a response

 

4. At some dose, ll of the subjects will achive a response.

 

5. When the curve is plotted, there will be some dose at which 50% of the population tested will have an achieved response. This dose is called the effective dose 50% or ED50

Term
Effecive Dose 50 (ED50)
Definition
On a frequency distribution, the point at which 50% of the population tested has achieved a response
Term

Lethal Dose 50

 

How is it determined?

Definition

Lethal Dose 50 (LD50): Is the point on the frequency distribution where 50% of people have had a deadly reaction due to the dosage

 

Not determined in animals; instead we determine the maximum tolerated dose in humans

Term
Therapeutic Index: Concept of a large therapeutic index being associated with a safer drug is used. Why?
Definition

Therapeutic Index is LD50 divided by ED50

 

Larger the TI, the safer the drug.

 

Ex: If a Drugs ED is 50mg but the LD is 100mg - the TI is only 2 - meaning there is a severe chance of overdosing

 

Ex: If a drugs ED is 50mg, but the LD is 1,000mg - the TI is 20 - meaning that a person would need to take 20 times the ED for the drug to become lethal - this is a safer drug

Term
Toxicity
Definition
An undesirable or dangerous effect of a drug brought about by high drug levels
Term
Side Effect
Definition
An undesirable effect of a drug that occurs at therapeutic levels of the drug and is the result of teh interaction ofteh drug with a receptor
Term
Allergic Response
Definition
A response to a drug that is mediated by the immune system
Term
Choice of a particular drug is usually dictated by ______________
Definition
the side effects,
Term

A frequency distribution curve for an antihypertensive agent shows an ED50 of 10 mg when the response is defined as a 10% lowering of blood pressure. What would happen if the response definition were changed to a 25% lowering of blood pressure?

A. The curve will shift to the right (toward higher doses)

B. The curve will shift to the left (towards smller doses)

C. The cuve will not change

D. The curve will broaden

Definition
A. The curve will shift to the right (towards higher doses)
Term
What response does the immune system produce when responding to an allergic reaction?
Definition

Anaphylaxix, rashes, hives

 

Patients should discontinue the drug right away

 

The patient could be given another drug that produced the same therapeutic effect in the hope that he/she would not be allergice to the new drug

Exception to this is an allergic reaction to nonsteroidal anti-inflammatory agents (NSAIDs), such as aspirn on ibuprofen

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