Intro to Pharamacology Flashcards

1
Q

study of substances that interact with living systems through chemical processes, especially by binding to regulatory molecules and activating or inhibiting normal body processes

A

Pharamacology

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q
  • what the BODY does to the DRUG
  • great practical importance in the choice and administration of a particular drug for a particular patient e.g. renal function
A

Phamokinetics

Comes into play with choosing drug

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q
  • what the DRUG does to the BODY
  • determines the group in which the drug is classified e.g. beta blockers
  • Like mechanism of action
A

Pharmacodynamics

Drug to Body, determins class of drugs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the 4 elements of pharmacokinetics?

A
  1. Absorbtion
  2. Distribution
  3. Metabolism
  4. Excretion
    ADME

Metabolims & Excretion are both elemination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Where do many orally administered medications pass through first after gut?

A

The liver then into plasma compartment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What part of the drug can enter the free tissues or site of action receptors?

A

Only the free drug can exit the plasama compartment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Injection of the drug into tissue

A

Intramuscular administration of drug

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Injection of the drug straight into the blood; plasma

A

Intravenous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

WHat are the 3 routes of drug administration?

A
  1. Oral
  2. Intramuscular injection
  3. Intravenous injection
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Explain the time course of drug action

A
  1. Take drug, drug gets absorbed absorption phase
  2. Drug concentration increases to peak
  3. Drug gets distributed around body distribution
  4. Drug is excreted & metabolized elimination phase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the 4 diffrent ways drugs can cross memebranes?

A
  1. Aqueous diffusion
  2. Lipid Diffusion
  3. Special carries
  4. Endo/Exocytosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What kind of drug permeation?

Drugs may diffuse passively through aqueous channels in the intercellular junctions (eg, tight junctions,

A

Aqueous Diffusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What kind of drug permeation

lipid soluble drugs pass through lipid cell membrane

A

Lipid Diffusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What kind of cell permeation?

Drugs with the appropriate characteristics may be transported by carriers into or out of cells

A

Special Carrier Diffusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What kind of drug permeation

Very impermeant drugs may also bind to cell surface receptors (dark binding sites), be engulfed by the cell membrane ____ , and then released inside the cell or expelled via the membrane-limited vesicles out of the cell into the extracellular space____

A

Endocytosis & Exocytosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What 5 thing does the rate and amount of absorbtion of a drug depend on?

A
  1. Local blood flow at site of admin (more flow= absorb better)
  2. Lipid Solubility (more lipid soluble easier to cross membrane)
  3. Molecular size (smaller passes esier throguh membrane)
  4. Local pH & Drug ionization (ionized drugs will not cross membrane)
  5. Total Surface Area of Absorbtion (More SA beter)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Where is the primary site of absorbtion for most oral drugs? why?

A

The small intestine
* It has vili that increase SA for absorbtion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

fraction of unchanged drug reaching the systemic circulation following administration by any route

A

Bioavailability

Expressed in %

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the bioavailibility of oral administered drugs? How about IV?

i.e How much will end up in systemic circulation

A

Oral= 75% bioavailable
IV= 100% always

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

metabolism of orally administered drug in the liver BEFORE it reaches the systemic circulation

A

First-Pass Effect
First-Pass Elemination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the result of a high first pass effect?

A

Decreased in bioavailibity
less reaches the systemic circulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What Route of Admin?

PROS
* Conveinient
* Large surface area for absorbtion
CONS
* Drug metabolims
* Incomplete absorbtion
* First pass effect
* GI upset

A

Oral (PO)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What route of admin?

PROS
* Direct
* No First pass effect
* Slow infessions of rapid onset of action
* Esier to titrate does
CONS
* Req IV acess
* Hard to remove
* Vascular injury

A

Intravenous IV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What route of admin?

PROS
* To specific organs; brain & heart
CONS

A

Intra-arterial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What route of admin?

PROS
* Good for depot storage (if oil based)
* Rapi onset of action
CONS
* Pain at site of infection

A

Intra-muscular (IM)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What route of admin?

PROS
* Non irritating small volumes
* Even slow absorbtion
* Adrenaline in local anesthetics
CONS
* Paina at site of infection

A

Subcutaneous (SC)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What route of admin?

PROS
* Conventiant
* Localizied
* Limited systemic absorbtion
CONS
* Effects limited to area of application

A

Topical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What route of admin?

PROS
* Immediate action in lungs
* Rapid delivery to blood
* Local or systemic action
CONS
* Must be in gas, vapor, or aerosol form

A

Inhalation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What route of admin?

PROS
* Rapid onset of action
* No first pass effect
CONS
* Must be lipid soluble

A

Buccal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What route of admini?

PROS
* Direct application
* rapud onset of action
CONS
* Injection at site of application
* Delayed onset of action

A

Tansdermal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

relates the amount of drug in the body to the concentration of drug (C) in blood or plasma

A

Volume of Distribution

C= concentration of drug in blood
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What does a high volume of distribution signify?

A

Means that most of the drug concentration is enteing the extravascular tissue.

high amount of drug in the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What affects Vd?

A

Affected by tissue and plasma binding and to which it binds more strongly too.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What does a low volume od distribution signify?

A

Most of the drug concentration is in the vascular compartment (blood)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

If a drug is highly bound to plasma protien what is trend in VD

A

Low value of distributuion because it is stuck in the vascular compartment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What are the ways in which drugs are bound?

A
  1. Free
  2. Bound to plasma protiens (albumin(
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Why is it dangerous to administer two drugs are highly bound to plasma protein?

A

Discplacement of one or the other drug from plasma protiens can **result in toxicitiy. **

monitor pt. more

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Only ____ can distribute into tissues and exert its action

A

free drug

39
Q

What are some principles of drug protein binding

A
  • Affinity of protien binding site (irreverisble?)
  • Saturation of binding site (highly bound + loose= toxicity)
  • Decreased albumin concentration (ex. liver faliure)
  • Competition for binding sites & substrates
  • Drug interactions
40
Q

Drug will accumulate until the amount of drug administered per unit of time is EQUAL to the amount eliminated per unit of time

Plateu

A

Steady State Concentration

Plasma concentration are at steady state

41
Q

At what halft life does steady state normally occur?

A

At about 4-5 half lifes, plasma concentration reaches Css

90 then 100%

42
Q

Single large dose of druge used to raise the plasma concentration to a therapeutic level more quickly than would occur through repeated smaller doses—helpful when it takes a long time to reach steady-state

A

Loading Dose

43
Q
  • Most drug dosing regimens
  • maintain a steady state of drug in the body, ie, just enough drug is given in each dose to replace the drug eliminated since the preceding dose
A

Maintenence Dose

44
Q

type of elemination

Biotransformation, body making drug more water soluble so it can leave!

**lipophillic to hydrophyllic*

A

Metabolism

45
Q

There are two phases in the metabolisms P1 & P2 where do they mainly occur?

A

The liver 2

46
Q

What is the first route of metabolims a drug can take after absorbtion?

A

Straight through phase 1 and then conjucated in phase 2.

47
Q

What is the second route of metabolims a drug can take after absorbtion?

A

Enters phase one and splits into
* Drug metabolite with modified activity
* Inactive drug metabolite

They then anter phase 2 and conjugate

48
Q

What is the third route of metabolims a drug can take after absorbtion?

A

It can go straight through phase 1 and 2 and striaght to elemination. Excreted unchanged in the urine.

49
Q

metabolism

What are the 3 elements of Phase 1 and what is the main purpose?

A
  1. Oxidation
  2. Reduction
  3. Hydrolysis

Increasing water solubility of the drug for excretion

50
Q

How does phase 1 of metabilims increase water solubility?

A

By adding or unmasking a polar functional group
OH, −NH2, −SH

51
Q

Metabolism

What enzymes mediate Phase 1?

A

Cytopchrome p450 liver enzymes

52
Q

Metabolism

What is the most common Cytochrom p450 enzyme that mediates phase 1 of metabolism?

A

CYP3A4

other Isoforms of Cytochrom P450

53
Q

Metabolism

What reaction occurs in Phase 2?

A

Conjucation reactions

54
Q

Metabolism

When an endogenous substrate, combines with newly added functional group to form a highly polar functional group

glucuronic acid, sulfuric acid, acetic acid, or an amino acid

A

Phase 2 of Metabolism

Further increases water solubility and elimination

55
Q

Why do we look at all the isoforms of Cytochrom P450?

A

Use of drugs can induce or inhibit certain isoforms.

56
Q

Result from?

  • Increased synthesis or decreased rate of degradation of p450
  • Accelerates metabolism of drug
  • Results in decreased effect
  • May increase toxicity of drugs that are transformed to reactive metabolites
A

Induction of the Cytochrome 450

57
Q

Results from?

  • Bind to p450 enzyme (sometimes irreversibly)
  • Decreases metabolism of drug or endogenous substances
  • Results in increased effect/toxicity
A

Inhibition of Cytocrhome 450

58
Q

Amiodarone is an inhibitor of CYP2C9 and CYP3A4 which inhibits the metabolism of Warfarin which does what?

A

Increases the risk of bleeding caused by elevted levels of Warfarin in the body

59
Q

Carbamazepine is an inducer of CYP3A4 which induces more metabolims of oral contraceptives which does what?

A

Increases risk of unplanned pregnancy caused by decreaed levels of the oral contraceptive (metabolized!)

60
Q

metabolism

what are the 6 phase two reactions?

A
  1. Methylation
  2. Sulfation
  3. Acetylation
  4. Glucoronidation
  5. Glucothionine Conjucation
  6. Glycine Conjucation

MSA-GGG

61
Q

Elimiation 2.

What are the 3 main routes of excretion

A

KIDNEY
1. Glomerular filtration
2. Tubular secretion
3. Passive Excretion

62
Q

If somthing is not very water soluble where will it most likely be excreted out of?

A

Biological stool

63
Q

Why do you have to be cautious when administering drugs to a pregnant newly birthed mother?

A

Drugs can be excreted through breast milk!

64
Q

Elemination rate

Estimates in creatine clearence (CrCl)

A

Cockroft-Gault equation

Depends on renal function

Age, ideal body weight
65
Q

indicates the time required to attain 50% of steady state—or to decay 50% from steady-state conditions.

A

Half Life

Useful in designing drug dosage regimines

66
Q

EX. half life is 10 hours.
* How long to reach stead state?
* How long to eliminatr?

A
  • 40-50 hours for both either way
67
Q

What is the goal of eleminatinon?

A

goal of metabolism is to de-toxify drugs, and make them either more water soluble (for excretion in the urine) or more fat soluble (for excretion in the bile, and then into the feces).

68
Q

any substance that brings about a change in biologic function through its chemical actions

A

Drug

69
Q

target molecule in the biologic system that plays a regulatory role

A

Receptor

70
Q

a compound that binds to a receptor and produces the biologic response by activating the receptor

A

Agonist

71
Q

a compound that binds to a receptor but does not activate generation of a signal

A

Antagonist

Interferes with the agonist ability to activate the receptor, doesnt generate a signal, no effects on its own, simply a stop

72
Q

Explain a competative antagonist

A

Maximal effect reached but at higher doses of agonist

The agonist and antagonist compete for site of receptor but the antagonist is not covalantely bound so it comes off and allows for agonist binding.

73
Q

Explain non-competative agonist

A

Reduced maximal effect even at high doses of agonist

  • Irreverisble
  • Allosteric
74
Q

Explain mechanism of irreversible non-competative inhibitor

A

The antagonist covalantely bonds to the receptor site blocking agonist and there lowering max effect

75
Q

Explain mechanism of allosteric non-competative inhibitor

A

The antagonist binds to site that is not the receptor, changing the shape of receptor site and **preventing binding of agonist. **

76
Q

Drug Receptor interaction

Much more rapid maximal effect

A
  • Agonist
  • Allosteric activator
77
Q

Drug Receptor interaction

Normal response

A

Only an Agonist

78
Q

Drug Receptor interaction

Delayed incresed, but eventually reaches maximal effect (still less)

A
  • Agonist
  • Compentative inhibitor
79
Q

Drug receptor interaction

Drug never reaches the steady state

A
  • Agonist
  • Allosteric Inhibitor
80
Q

produces the biologic response but cannot produce 100% of the response even at high doses

A

Partial Agonist

Some designed on purpose.

81
Q

What is an example when you prescribe a partial agonist?

A

Trying to get some one off opiod addiction, does not provide the high but also prevents withdrawls.

82
Q

____ Agonist that have the oppiste effects from a full agonist

decrease basline receptor

A

Inverse Agonist

83
Q

What are the 3 drug receptor bonds

A
  1. Covalent (strong)
  2. Electrostatic (weak)
  3. Hydrophobic (weakest)
84
Q

What bond?

very strong and in many cases not reversible under biologic conditions

A

Covalent

85
Q

What bond?

weaker then covalent bonds and more common

vary from relatively strong linkages between permanently charged ionic molecules to weaker hydrogen bonds and very weak induced dipole interactions such as van der Waals forces

A

Electrostatic

86
Q

What bond?

usually quite weak
important in the interactions of highly lipid-soluble drugs with the lipids of cell membranes

A

Hydrophobic

87
Q

Drugs that bind through weak bonds are more ____ than drugs that bind in strong bonds.

A

weak bonds= selective drug
* weak bonds require precise fit

88
Q

the measure of drug safety

A

Theraputic Index

89
Q

High TI vs Low TI?

A
  • High/wider TI= safer
  • Low/narrower TI= less safe

TD50/ED50 4+ good

The further the TD 50 and ED50 the higher the TI

90
Q

The maximal response that a drug can produce

A

Efficacy

91
Q

The measure of the dose that is required to produce the response

A

Potency

92
Q

Drug that requires smaller does and stops issue entirly

A

More potent drug

93
Q

Drug that requires higher does and only stops issue 60%

A

Less efficacy and less potancy

94
Q

The **lower the EC(50) **which is the concentration of drug to reach 50% response

what does this** mean for potency?**

A

The higher the potency, drug reaches EC50 faster!