Pharmacology Basics Part 2

Question 1

Pharmacokinetics

Answer 1

All about What the/our body does to the drug
How body processes med

Question 2

Pharmacokinetics: 4 processes that are part of it

Answer 2

Absorption: getting drug to blood - most in SI, into bloodstream, into portal vein, processed and metabolized by the liver, put out into systemic circ and there distributed to tissues, excreted by kidneys and happens over and over again until all drug been broken down and excreted from body
Distribution: getting drug to tissues
Metabolism: breaking drug down
Excretion: getting drug out of body

Question 3

Absorption

Answer 3

Getting drug from outside into the bloodstream to be distributed to tissues - lot talking about absorption and pertinent is route
Many factors influence drug absorption:

Question 4

Many factors influence drug absorption: (Absorption)

Answer 4

Route - big one; how getting into body
Drug properties
Patient properties

Question 5

Drug properties (Many factors influence drug absorption: (Absorption)

Answer 5

Molecular size, lipid solubility, pH

Question 6

Patient properties (Many factors influence drug absorption: (Absorption)

Answer 6

Surface area of absorptive surface, blood flow to site of absorption

Question 7

Oral route

Answer 7

Majority meds given via this route; easier route to do; not invasive and cheaper to make oral drugs than other preps
Some medications are absorbed in the stomach, but most drugs are absorbed in the small intestine and into portal vein - because of this metabolic process happens immediately after absorbed get through liver and get metabolized before sent out to systemic circ (first pass effect) - onset slightly delayed for oral drugs relative to other routes for that reason; whole process takes place before gets into systemic bloodstream where exerts its effects
Due to first-pass metabolism, the onset of action for most oral drugs is 30-60 minutes - lot things that impact absorption so not exact science
Many diff factors affect drug absorption via oral route (next slide)

Question 8

Some medications are absorbed in the stomach, but most drugs are absorbed in the small intestine and into portal vein - because of this metabolic process happens immediately after absorbed get through liver and get metabolized before sent out to systemic circ (first pass effect) - onset slightly delayed for oral drugs relative to other routes for that reason; whole process takes place before gets into systemic bloodstream where exerts its effects (Oral route)

Answer 8

Must pass through lipoid cell membranes to get to blood stream

Question 9

Due to first-pass metabolism, the onset of action for most oral drugs is 30-60 minutes - lot things that impact absorption so not exact science (Oral route)

Answer 9

See metabolism slides

Question 10

Factors affecting absorption via oral route (Oral route)

Answer 10

Each impact absorption
Molecular weight:
Lipid solubility:
Surface area of gastrointestinal mucosa
Blood flow to gastrointestinal system
Rate of gastric emptying
Oral preparation:
Administration of multiple drugs simultaneously (interaction)
Foods and fluids administered with drugs (binding)

Question 11

Molecular weight: (Factors affecting absorption via oral route (Oral route)

Answer 11

Too big, can’t pass membrane (alt route)
Composition of some drugs is just too big to pass through lipid membrane that drugs need to do to be absorbed via the oral route - get from GI tract into bloodstrea and pass through lipid bilayer membrane and some too big and cannot get into bloodstream and not distributed anymore are worthless; stay in GI tract and leave body so most circumstances need be given alternate route

Question 12

Lipid solubility: (Factors affecting absorption via oral route (Oral route)

Answer 12

Small and highly lipid soluble drugs rapidly through membrane (passive diffusion) - highly lipid soluble pass through membrane
Low lipid-soluble drugs: facilitated diffusion, active transport, pinocytosis
Highly water soluble - dissolves before absorbed correctly - use alternate route

Question 13

Surface area of gastrointestinal mucosa (Factors affecting absorption via oral route (Oral route)

Answer 13

That is available for absorption
Certain GI probs - atrophic gastritis, gastric bypass surgery affects way absorb meds

Question 14

Oral preparation: (Factors affecting absorption via oral route (Oral route)

Answer 14

Liquid&raquo_space;»> enteric coated tablet (see next slide)
Way prep effects how fast absorbed

Question 15

Administration of multiple drugs simultaneously (interaction) (Factors affecting absorption via oral route (Oral route)

Answer 15

2 drugs together at same time impacts absorption of one drugs for some reason - some drug-drug interactions

Question 16

Foods and fluids administered with drugs (binding) (Factors affecting absorption via oral route (Oral route)

Answer 16

Ca - bind with lot drugs; not take drugs with milk products because have lot Ca; may be absorbed, not absorbed, stays in GI, not do thing, not do therapeutic effect

Question 17

Gen rules for oral drugs

Answer 17

Administer oral drugs 1 hour before or 2 hours after a meal with full glass (about 8 oz.) water; best taken on empty stomach - taking out any probability drug-food interaction; allow for best absorption; take with full glass of water - help dilute med and help decrease gastric irritation that pat might have
Assess for drug effects 30-60 minutes after administration/given; wait 60 min so enough time to work and on safe side

Question 18

Sublingual

Answer 18

Absorbed into highly vascular tissue under tongue; really rapid action
Put underneath tongue and dissolves
Underneath tongue - very vascular: dissolves and into bloodstream quickly
Want rapid that do at home and want take effect quickly
Fast action

Question 19

Topical

Answer 19

Delivers drug directly to affected area (skin, eye, ear, inhaler lungs, etc.)
Typ have minimal systemic absorption - once systemic absorption more likely have more adverse effects
For local effects

Question 20

Transdermal

Answer 20

Provides constant rate of drug absorption
More rare route
Always apply to intact skin (broken skin increases absorption)

Question 21

Intravenous (IV)

Answer 21

Full strength; immediate onset and fully absorbed; more likely to cause toxic effects
If administering more than 1 drug at same site, must be compatible; talk how to give multiple meds through 1 IV line but make sure can give together - need compatible - mix well - if not clog and precipitate in line; when mix in same line make sure are compatible
Giving full effect of the drug
Straight into bloodstream; no first pass effect; most potent form of med can give; be esp diligent when giving something IV
Pretty immediate circ because in vein and pumped out to systemic circ
Vein - drops to heart and pumps out to systemic circ and distributed everywhere in body; Lot drugs can be caustic - meaning can cause damage - arteries seem to get damaged easier - going away from heart less overall volume and not diluted blood when traveling from heart when more volume

Question 22

Intramuscular (IM)

Answer 22

Absorbed directly into capillaries in muscle and sent into circulation
Men more vascular muscles than women; men reach a peak level faster than women

Question 23

Slowly absorbed; timing of absorption varies depending on fat content and state of local circulation
Increased adipose tissue = decreased absorption (less capillaries)
Good for certain things but less predictable due to pat variation - one variations is amount of adipose tissue; more adipose tissue someone has less absorption get from med because not as much blood flow to tissue and need really good blood flow to area for drug be absorbed into bloodstream
Excess adipose tissue not allow good absorption; hard know when becomes issue - means people have sig amounts adipose tissue need higher dose SQ meds because not absorb as effectively

Answer 23

Subcutaneous (SQ)

Question 24

Means Amount of drug that reaches systemic circ through distribution; able get distributed to tissues and cause an effect
IV: 100% absorption - going right into the bloodstream: 100% bioavailable
IM/SQ: 100% absorption: <100% bioavailable
Oral: <100% absorption: 0-70% bioavailable for distribution so not all of it - all factors impact absorption so not ever have 100% and varies depending on pat and on factors present in pat for oral route; also have consider first pass effect; when factors and first pass effect not all available reaching tissues
IV and oral dose not same for pat for any drug; IV dose would be less because getting full strength and not having all factors affecting absorption and no first pass effect that happens before put into circ
If figure out not very bioavailable move to diff route where more effective and more bioavailable in drug phases when developing a drug

Answer 24

Bioavailability

Question 25

When trying to determine why the desired therapeutic effect is not being seen with an oral drug, the nurse should consider which factor?
A.The blood flow to muscle beds
B.Food altering the makeup of gastric juices
C.The weight of the patient
D.The temperature of the peripheral environment

Answer 25

Answer: B
Rationale: Changes in stomach pH can alter the absorption of an oral drug. The absorption of an oral drug is not impacted by body weight (SQ), blood flow to muscles (IM) or temperature of the environment.
ORAL DRUG/ROUTE
Looking at oral route; something specific to taking drug orally

Question 26

Once drug enters systemic circ has get distributed to have an effect; has to make its way to diff tissues - what this is about
Movement of the drug to body’s tissue (results in therapeutic and adverse effects)
Increased volume of distribution: faster onset; shorter duration
Decreased volume of distribution: slower onset; longer duration

Answer 26

Distribution

Question 27

Movement of the drug to body’s tissue (results in therapeutic and adverse effects) (Distribution)

Answer 27

See slides on pharmacodynamics - what drug does to body; how drugs exert their effects

Question 28

Lots of these
Blood flow to organs/tissues
Ability to cross blood-brain barrier or fetal/placental barrier -
Drug properties

Answer 28

Factors affecting distribution

Question 29

Blood flow to organs/tissues (Factors affecting distribution)

Answer 29

Distribute to tissues - has use arteries
Areas of rapid perfusion/distribution: heart, liver, kidney, brain - typ for body; rapidly distribute blood to vital organs and helps us live
Areas of slow distribution: muscle, skin, fat - typ for body; not vital to life
Tissue ex: PAD (lack blood flow to lower extremities due to ischemia) decreases blood flow to lower extremities - not good blood flow to LE and if have infected ulcer on foot and need systemic antibiotics because topical not work, if do IV not do well in treating infection if have this because not have good blood flow to area that is infected which is where need antibiotic to go so hard treat the area

Question 30

Ability to cross blood-brain barrier or fetal/placental barrier - (Factors affecting distribution)

Answer 30

distribution: can this drug cross that blood-brain barrier and not always bad thing; sometimes want it to cross like sedative - need cross barrier to have effect; sometimes crosses barrier and not want to and is an adverse effect; fetal/placental barrier - drugs can cross barrier

Question 31

Drug properties (Factors affecting distribution)

Answer 31

Affects distribution
Protein binding (albumin - protein; most abundant protein in plasma)
Water solubility vs. lipid solubility

Question 32

Protein binding (albumin - protein; most abundant protein in plasma) (Drug properties (Factors affecting distribution)

Answer 32

Some drugs Highly protein bound (means want bind to proteins like albumin); relevant because if drug wants be highly protein bound it cannot pass through other membranes because it gets too big; when drug binds to protein, molecule of drug not able get distributed to tissues and takes away for an effect when binds to the protein
Chronic liver disease -
Drug can bind to albumin and no longer do job; unbound can be distributed

Question 33

Chronic liver disease - (Protein binding (albumin - protein; most abundant protein in plasma) (Drug properties (Factors affecting distribution)

Answer 33

low albumin and liver can no longer make protein: albumin - affects water balance and keeps in vascular space and contributes to ascites
If in end stage liver disease and low albumin levels: affects highly protein bound drug - they have more free drug available because not as much albumin to bind to and more free drug available and more likely experience toxic effect of drug
Means: have monitor pats closely; need to vigiley monitor every pat - esp if have altered albumin levels can be toxic when on any drug that is highly protein bound; provider should lower dosehave
Low albumin levels means more drug available and higher risk for toxicity

Question 34

Water solubility vs. lipid solubility (Drug properties (Factors affecting distribution)

Answer 34

Highly water-soluble drugs stay in blood stream; go more places
Highly lipid-soluble drugs more readily pass lipid cell membranes and deposit in adipose tissue

Question 35

Liver is the primary site/organ for metabolizing drugs
Metabolic activity may be decreased in some patients
Liver transforms some drugs to active form (prodrug)
Nurse:

Answer 35

Metabolism (aka biotransformation)

Question 36

Liver is the primary site/organ for metabolizing drugs (Metabolism (aka biotransformation)

Answer 36

Hepatic microsomal enzyme system (P-450 system) - specific enzyme sys that does lot work of metabolism - alterations in enzyme sys can result in changes to drug effects
Liver imp for metabolism drug; helps with excretion (done by kidneys) - breaks down and gets ready for excretion by kidneys
Changes in hepatic microsomal enzymes can affect drug metabolism

Question 37

Liver imp for metabolism drug; helps with excretion (done by kidneys) - breaks down and gets ready for excretion by kidneys (Liver is the primary site/organ for metabolizing drugs (Metabolism (aka biotransformation)

Answer 37

Inactivates/breakdown drug for excretion; some to active form
Some drugs - not many - transform drug to its active in addition to breaking it down (called prodrugs) - need activate to do any job in the body

Question 38

Metabolic activity may be decreased in some patients
(Metabolism (aka biotransformation)

Answer 38

Infants (immature liver - not readily breakdown drugs as easily, impact dose given to an infant) and elderly (liver wears down and quits working; not metabolize drugs as well; give lower doses of med because not metabolize as readily); genetic disorders; severe liver disease (adv cirrhosis not metabolize drugs as well)
Dosages reduced in decreased liver function to prevent toxicity - monitor liver func before given drugs; look at liver func tests (ALT, AST, LFOX); make sure have properly working liver and make sure not suffering injury to liver because many meds can damage because liver working to metabolize and liver injured in process and make sure not suffering liver toxicity

Question 39

Nurse: (Metabolism (aka biotransformation)

Answer 39

Liver disease is a caution/contraindication when administering certain drugs
Monitor liver functions in pat before give drugs to avoid drug toxicity or injury to liver - check liver func tests

Question 40

Enzyme induction
Enzyme inhibited

Answer 40

Metabolism: hepatic enzyme sys probs - alter metabolism

Question 41

Enzyme induction (Metabolism: hepatic enzyme sys probs - alter metabolism)

Answer 41

Inducer
Increased activity of enzyme system by presence of first drug; one makes enzyme sys work more efficiently and what does is speeds metabolism of second drug using same enzyme system; cannot reach needed therapeutic levels
One drugs make sys work more efficiently and speeds up metabolism of drug - listed as drug-drug interaction; speeds up metabolism and drug not metabolized more quickly than anticipated so broken down faster so less drug available to be distributed to tissues so might not see therapeutic effect
take one drug and speeds up enzyme sys prob is drug-drug interaction (taking 2 drugs) and interactions occurs because how liver enzymes affected; second drug broken down much quicker than anticipated so not in bloodstream as long and not distributed because broken down and inactivated by liver and not see effect thought
Why some drugs cannot be taken together

Question 42

Enzyme inhibited (Metabolism: hepatic enzyme sys probs - alter metabolism)

Answer 42

Some drugs inhibit enzyme system-make less effective
Drug will not be broken down for excretion
Blood level of drug increases to toxic level
Inhibits those enzymes so slows down enzyme activity and enzymes responsible for metabolizing/breaking down other drug and if enzymes not do that because suppressed more drug in bloodstream because not broken down, run risk for toxicity
Too much of the drug level
Comes into play with drug-drug interaction

Question 43

It is metabolism
Happens mostly with oral routes; some other routes affected by this but not given often
Give drug orally goes into stomach and most drugs absorbed in SI and absorped into portal vein which feeds directly into the liver and goes through first pass effect: heavily metabolized by liver and after drug shoots it into systemic circ - out vein into heart to systemic distribution for absorption - part reason for <100% bioavailability - goes through liver gets to before systemic circ; research studies - how heavily metabolized - if heavily metabolized increase dose for therapeutic effect; not as much might keep with lower dose because not metabolized as much with this effects; other routes beside oral route skipping this because going into gen circ

Answer 43

Metabolism: first pass effect (oral route)

Question 44

Kidneys are the primary organ/site for excretion of drugs from body - liver breaks it down; circulated into bloodstream, kidneys excrete and it gets out of body
Kidney dysfunction
Nurse: monitor kidney function to avoid drug toxicity or AKI - make sure functioning correctly; if have known kidney disease may need do lower dose of the drug because body not excrete as well effectively and more remain in blood stream so need lower dose; many meds can be nephrotoxic - monitor kidney func to make sure not injuring kidneys
Liver/bowel are secondary site for excretion

Answer 44

Excretion

Question 45

Kidney dysfunction (Excretion)

Answer 45

Drugs not excreted effectively; reach toxic levels

Question 46

Liver/bowel are secondary site for excretion (Excretion)

Answer 46

Drugs processed by liver, released into bile, eliminated in feces

Question 47

Dynamic Equilibrium = Actual concentration drug reaches in body
All 4 processes of pharmacokinetics: lead to a dynamic equilibrium of a drug
all elememnts play role/Processes are key elements in determining amount of drug (dose), frequency of dose repetition (scheduling) required to achieve therapeutic minimal effective concentration for desired length of time. - figure out reacts, how normally excreted, how fast metabolized to figure out dose and scheduling - looked at when do studies of drug in diff phases

Answer 47

Dynamic equilibrium

Question 48

All 4 processes of pharmacokinetics: lead to a dynamic equilibrium of a drug (Dynamic equilibrium)

Answer 48

Absorption from site of entry
Distribution to active site
Metabolism in liver
Excretion from body

Question 49

Time for drug to elicit a therapeutic response
When drug starts to produce an effect; oral 30-60 min because have go through first pass effect and get distributed to tissues, etc; start having a therapeutic effect

Answer 49

Onset

Question 50

Time for a drug to reach its maximum therapeutic response

Answer 50

Peak

Question 51

Time a drug concentration sufficient to elicit therapeutic response
When no longer have impact and therapeutic effect ends then duration of effect ends

Answer 51

Duration

Question 52

Time for amount of drug in body to decrease to one-half peak level; depend on how easily metabolized it is and how easily excreted it is; determined by lot things: determined by how fast absorbed, quickly broken down by liver, excretion, etc - all processes of pharmacokinetics go into
Most drugs eliminated in 4-5 half-life’s; length of half-life varies

Answer 52

Half-life

Question 53

Therapeutic MEC = Amount of a drug that is needed to cause a therapeutic effect
Loading dose

Answer 53

Pharmacokinetics: minimal effective concentration (MEC)

Question 54

Therapeutic MEC = Amount of a drug that is needed to cause a therapeutic effect (Pharmacokinetics: minimal effective concentration (MEC)

Answer 54

Have give pats enough drug for it to do something; give enough to have effects
Happens at same point of onset because that when exerting effect to pat; enough amount of drug there to do something
Recommended dose of a drug is based on amount that must be given to eventually reach therapeutic MEC

Question 55

Recommended dose of a drug is based on amount that must be given to eventually reach therapeutic MEC (Therapeutic MEC = Amount of a drug that is needed to cause a therapeutic effect (Pharmacokinetics: minimal effective concentration (MEC)

Answer 55

Too much drug = toxic (poisonous) effects; likely experience toxicities - sometimes can be life threatening
Too little drug = will not produce desired therapeutic effects want

Question 56

Loading dose (Pharmacokinetics: minimal effective concentration (MEC)

Answer 56

Def: give a Higher dose than usually used for treatment to reach therapeutic MEC faster - to start pat off - so reach MEC faster; not want wait long time because could have stroke and give loading dose and elevates drug level quickly and then go to more reg schedule after
Subsequently maintained by using recommended dosing schedule
Not tie in with half-life
Pertinent for onset of effect; faster onset if use this which is its purpose; much quicker time to onset; makes onset quick which is its purpose to help pat

Question 57

Half-life
How drug attains and maintains therapeutic range (steady state)
Therapeutic window/range/index

Answer 57

Pharmacokinetics: half-life and therapeutic window/range

Question 58

Half-life (Pharmacokinetics: half-life and therapeutic window/range)

Answer 58

Time required for one-half (50%) of a given drug to be removed from the body (5 half-lives, 97% drug eliminated from body)
Greater half-life, longer it takes to excrete
Determines frequency and dosage
Want maintain therapeutic level

Question 59

How drug attains and maintains therapeutic range (steady state) (Pharmacokinetics: half-life and therapeutic window/range)

Answer 59

Repeated doses of drug are given
Drug accumulates in bloodstream
Plateau is reached
Amount administered equals amount eliminated

Question 60

Therapeutic window/range/index (Pharmacokinetics: half-life and therapeutic window/range)

Answer 60

Range of med that is deemed safe for a patient and produce some kind of an effect without having toxic effects; want stay in range for pat so benefit from drug but not above range so no risk for toxicity and now have too of the much of drug; most drugs have fairly large therapeutic window; most HCPs make educated guess and not become toxic for someone
Some drugs narrow therapeutic window meaning reach toxic effects easily - get toxic easily with certain drug and with those do blood level monitoring see how much in bloodstream at given time to ensure not already toxic or risk of becoming toxic soon

Question 61

Half-life examples

Answer 61

Drug dose = 100 mg
Half-life = 1 hour
1 hour = 50 mg
2 hours = 25 mg
3 hours = 12.5 mg
4 hours = 6.25 mg
5 hours = 3.125 mg
4-5 half lives with a low amount of drug relative to what started and basically eliminated from body
Every 2-3 hours given because need give enough so therapeutic so not dropped below therapeutic effect
Drug dose = 100 mg
Half-life = 5 minutes
5 minutes = 50 mg
10 minutes = 25 mg
15 minutes = 12.5 mg
20 minutes = 6.25 mg
25 minutes = 3.125 mg
Frequent dosing - shorter half-life; fall out therapeutic window quickly and need keep there
Have give more often - reload more often because falling out therapeutic window quickly and need keep them in there
Maybe q20min - not fall out therapeutic effect
Keep timing of the doses where it is supposed to be and deals with half-life and very imp to do with timing and half-life shorter; need keep level at therapeutic

Question 62

Order put in for draw them at specific times for some drugs - order for peak/trough level
Blood test performed to determine levels of drugs
Peak and Trough

Answer 62

Therapeutic drug monitoring

Question 63

Blood test performed to determine levels of drugs (Therapeutic drug monitoring)

Answer 63

Determine therapeutic range and avoid toxicity

Question 64

Peak and Trough (Therapeutic drug monitoring)

Answer 64

Tests to determine highest and lowest blood level of drug
More in acute care; drugs 1 time/3 months - not particular about timing - draw anytime of day but if peak/trough timing is imp

Question 65

Tests to determine highest and lowest blood level of drug (Peak and Trough (Therapeutic drug monitoring)

Answer 65

Trough
Peak

Question 66

Trough (Tests to determine highest and lowest blood level of drug (Peak and Trough (Therapeutic drug monitoring)

Answer 66

Lowest drug level in bloodstream needed to reach therapeutic range drawn 1 hour prior to start of next infusion
EX: Vancomycin
May wait until get this level back until next infusion if told
Timing matters sig - decisions about dose based on draw

Question 67

Peak (Tests to determine highest and lowest blood level of drug (Peak and Trough (Therapeutic drug monitoring)

Answer 67

Highest level of the drug in the bloodstream drawn 1 hour after infusion completed
Timing matters sig - decisions about dose based on draw

Question 68

Happens with certain pats - lot factors go into howa person processes/reacts to med: lots variables; need monitor pats closely because unpredictable between pats and days how react to med and process it
Individual human factors greatly influence effect of drug in body
No two people react in the same way to any given drug
Remember

Answer 68

Factors influencing drug effects

Question 69

Remember (Factors influencing drug effects)

Answer 69

Drug guides explain pharmacodynamics and pharmacokinetics of a drug, but most of that information is based on controlled studies of healthy adults - providers determining how much give is educated guess give to pats and not always 100% so much monitor closely
Dosage based on 150 pound adult - route, type, size pat

Question 70

Change day to day with pats, constantly monitor pat - affects all other drugs; indiv; always changing with drugs
Age (See lifespan)
Gender
Physiological Factors
Pathological Factors
Genetic Factors
Psychological Factors
Environmental Factors
Tolerance
Interactions

Answer 70

Factors influencing drugs effect

Question 71

Gender (Factors influencing drugs effect)

Answer 71

Depending on route giving med
Men – more vascular muscles; women-more fat cells- slow release

Question 72

Physiological Factors (Factors influencing drugs effect)

Answer 72

Diff drugs acts diff
Hydration (dehydration), acid-base, electrolytes

Question 73

Pathological Factors (Factors influencing drugs effect)

Answer 73

Disorders change conditions for drug (vascular, GI, liver, kidney disease, etc.)

Question 74

Genetic Factors (Factors influencing drugs effect)

Answer 74

Lack enzymes, cultural differences

Question 75

Psychological Factors (Factors influencing drugs effect)

Answer 75

Attitude: placebo effect, trust in HCP

Question 76

Environmental Factors (Factors influencing drugs effect)

Answer 76

Temperature, exercise, relaxed environment

Question 77

Tolerance (Factors influencing drugs effect)

Answer 77

Larger dose needed

Question 78

Interactions (Factors influencing drugs effect)

Answer 78

Two or more drugs

Question 79

Happen Any part pharmokinetic process and impact any drug
Site of absorption
During distribution/site of action
During metabolism
During excretion

Answer 79

Drug-drug interactions: altered effectiveness

Question 80

Site of absorption (Drug-drug interactions: altered effectiveness)

Answer 80

One drug prevents or accelerates absorption of another drug; prevent from absorbed and not absorbed effectively and not same therapeutic effect because what other drug did to it

Question 81

During distribution/site of action (Drug-drug interactions: altered effectiveness)

Answer 81

Drugs compete for binding site of another- one drug gets bumped off
Opposing mechanisms of action - agonist and antagonist (opp) - one drugs/both not act way should
Drugs with similar adverse effects

Question 82

During metabolism (Drug-drug interactions: altered effectiveness)

Answer 82

One drug stimulates or blocks metabolism of another drug
Hepatic enzyme sys - 2 drugs together can alter enzyme sys

Question 83

During excretion (Drug-drug interactions: altered effectiveness)

Answer 83

One drug competes for other to be excreted-leads to accumulation/toxicity

Question 84

Prevent absorption (with the oral route)
Increase or decrease drug’s effect (any route)

Answer 84

Drug-food interactions

Question 85

Prevent absorption (with the oral route) (Drug-food interactions)

Answer 85

Increased acid production- speeds breakdown of drug
Milk products: calcium binds to drugs, decreased absorption; come up a lot
Chemical reaction

Question 86

Chemical reaction (Prevent absorption (with the oral route) (Drug-food interactions)

Answer 86

Ex: Iron and Ca binds with tetracycline - avoid taking products with Iron/Ca because not absorb it and not have effect want to have

Question 87

Increase or decrease drug’s effect (Drug-food interactions)

Answer 87

Food affects liver enzymes actions

Question 88

Food affects liver enzymes actions (Increase or decrease drug’s effect (Drug-food interactions)

Answer 88

Ex: Grapefruit juice: affects liver enzymes up to 48 hours after ingested ; liver enzyme inhibitor ; leads to toxic effects of some drugs; inhibit enzymes responsibile for breaking down and drugs not broken down drugs as expected and can lead to toxic effects

Question 89

Types of adverse effects/rxns
Adverse effects: EX
Adverse effects: Toxic effects to organs
Adverse rxns: allergic rxns
Penicillin allergy
Angioedema
Stevens Johnson Syndrome
Allergic Rxns: nursing interventions

Answer 89

Adverse effects

Question 90

Types of adverse effects/rxns (Adverse effects)

Answer 90

Primary Actions/adverse effects
Secondary Actions/adverse effect
Toxicity
Allergic reactions

Question 91

Primary Actions/adverse effects (Types of adverse effects/rxns (Adverse effects)

Answer 91

Overdose; extension of therapeutic effect of drug/desired effect (ex – antihypertensive: primary AE hypotension; laxative: primary AE diarrhea) - means pat got too much drug for whatever reason; mean gave what norm range of drug and therapeutic effect greater than wanted to be
Dose adjustments

Question 92

Secondary Actions/adverse effect (Types of adverse effects/rxns (Adverse effects)

Answer 92

Side effects
Other things happen that are unwanted that go with the drug - hard time target what want to - give med go anywhere in bloodstream and target other tissues
Undesired effects produced in addition to pharmacologic effect (ex – nausea, vomiting, diarrhea, constipation)
Undesired effect must be tolerated

Question 93

Adverse effects: EX (Adverse effects)

Answer 93

Opportunistic infections (fungal): Destruction of the body’s normal flora; drugs can cause these
Blood dyscrasias: Bone marrow suppression - low count white cell and blood cells
Alterations in blood glucose
Alterations in electrolytes (common electrolyte abnorm: hyper-, hypokalemia; hyper-, hyponatremia)
Auditory damage
Central nervous system depression - not easily aroused, sedated, not aroused to voice, really severe sternal rub to get them awake
Photophobia: sensitivity to light
Photosensitivity: sensitivity to UV rays
Gastrointestinal effects (irritation): Nausea, vomiting, diarrhea (n/v/d)
Headache
QT prolongation increases risk for ventricular arrhythmias (Torsade) - some drugs can cause dysrhythmias that can be potentially fatal

Question 94

Auditory damage (Adverse effects: EX (Adverse effects))

Answer 94

Eighth cranial nerve are easily irritated and damaged by certain drugs
CM: Dizziness, ringing in the ears (tinnitus), loss of balance, and loss of hearing

Question 95

Headache (Adverse effects: EX (Adverse effects))

Answer 95

Related to action and dose-dependent; anti-hypertensives - vasodilation
Related to increased intracranial pressure
Idiosyncratic - lot times just happen
Many drugs cause headaches
Withdrawal

Question 96

Adverse effects: Toxic effects to organs (Adverse effects)

Answer 96

Organs most likely to suffer toxicity with meds
Liver
Kidney
Nervous system

Question 97

Liver (Adverse effects: Toxic effects to organs (Adverse effects)

Answer 97

CM: Fever, nausea, jaundice, urine dark orange or clay stool
Labs: elevated liver enzymes, PTT (bleeding time)

Question 98

Kidney (Adverse effects: Toxic effects to organs (Adverse effects)

Answer 98

CM: change urinary pattern (oliguria) - stop urinating when go to AKI
Labs: elevation BUN and creatinine

Question 99

Nervous system (Adverse effects: Toxic effects to organs (Adverse effects)

Answer 99

CM: looking at mainly Change behavior, looking at mainly level of consciousness, cognition

Question 100

Adverse rxns: allergic rxns (Adverse effects)

Answer 100

2 most common allergic rxns seen with meds
Anaphylaxis
Delayed Allergic Reaction

Question 101

Anaphylaxis (Adverse rxns: allergic rxns (Adverse effects)

Answer 101

Massive histamine release
Involves massive systematic response (histamine)
Clinical manifestations:

Question 102

Involves massive systematic response (histamine) (Anaphylaxis (Adverse rxns: allergic rxns (Adverse effects)

Answer 102

Leads to bronchoconstriction, shock, and death

Question 103

Clinical manifestations: (Anaphylaxis (Adverse rxns: allergic rxns (Adverse effects)

Answer 103

Hypotension, tachycardia, dyspnea, edema, hives, itching, respiratory or cardiac arrest

Question 104

Delayed Allergic Reaction (Adverse rxns: allergic rxns (Adverse effects)

Answer 104

Occurs hours to days after exposure/take med
Clinical manifestations
Not place where full blown anaphylaxis - localized to skin and joints

Question 105

Clinical manifestations (Delayed Allergic Reaction (Adverse rxns: allergic rxns (Adverse effects)

Answer 105

Diffuse Rash all over skin, hives, itching, swollen joints

Question 106

Penicillin allergy (Adverse effects)

Answer 106

Developed delayed allergic rxn

Question 107

Angioedema (Adverse effects)

Answer 107

Swelling under the skin of lips, tongue, anywhere in face and throat - dangerous for pat - if swelling and compromises airway then big issue - can have mild then not issues; so severe swelling so great in region then compromises ability breathe effectively
Listed for a lot of drugs where it is more common but this is rare overall

Question 108

Stevens Johnson Syndrome (Adverse effects)

Answer 108

Very rare potentially fatal drug reaction - rare adverse effect; lot drugs can cause this; can happen with any dose of a drug; life threatening and very serious but more rare
May occur with OTC or prescription meds
Flu-like symptoms, followed by a painful red or purplish rash that spreads and blisters
Skin blistering and lot systemic probs
Extension of Stevens Johnson Syndrome

Question 109

Extension of Stevens Johnson Syndrome (Stevens Johnson Syndrome (Adverse effects)

Answer 109

Toxic epidermal necrolysis (TENS) - rxn to drugs; another serious but rare

Question 110

Allergic Rxns: nursing interventions (Adverse effects)

Answer 110

Need know what do
First:
Next: - stopped admin and put O2 on them if having difficulty breathing

Question 111

First: (Allergic Rxns: nursing interventions (Adverse effects)

Answer 111

Stop administration of the medication immediately - oral drug and gave it cannot do anything in terms stopping it can cancel rest doses; IV infusion med and have glimpse have an allergic rxn stop admin immediately because less drug less severe rxn be and
Apply oxygen (if needed) - any difficulty breathing get O2 on them and take VS

Question 112

Next: - stopped admin and put O2 on them if having difficulty breathing (Allergic Rxns: nursing interventions (Adverse effects)

Answer 112

Call rapid response team if severe if in acute care - assess pat and see if more IVs need be started; need be done immediately to stabilize pat; can be variety of things: order IV fluids - help flush out med and dilute it bloodstream more - order antihistamine (Benadryl) to combat allergic rxn
Notify primary care provider - get time and hands free notify what happened once pat stabilized
Administer intravenous fluids as ordered
Administer antihistamines as ordered

Question 113

A woman has recently been prescribed several rounds of antibiotic therapy. She calls the clinic with complaints of vaginal drainage and itching. The nurse determines which statement is most correct?
A.The client needs to perform perineal care more often
B.The client has developed a superinfection due to the antibiotics
C.The client has developed a sexually transmitted disease
D.The client will need to a new antibiotics to treat this new infection

Answer 113

Answer: B
Rationale: Antibiotics kill bacteria but also harm the normal flora of the body. When normal flora is destroyed the body becomes susceptible to fungal infections.

Question 114

Knowing that a client is taking a loop diuretic and is at risk for developing hypokalemia, the nurse would assess the client for which clinical manifestations?
A.diarrhea and flatulence
B.hypertension, headache, and cold and clammy skin
C.decreased urinary output and yellowing of the sclera
D.weak pulse, low blood pressure, and muscle cramping

Answer 114

Answer: D
Rationale: Potassium helps support muscle contraction, heart function and blood pressure. Hypokalemia will result in weak pulse, low BP and muscle cramping.
Looking for manifestations of hypokalemia - CARDIAC

Question 115

The nurse is evaluating medication therapy. Which assessments indicate potential toxicity to the kidneys? Select all that apply.
A.Bladder scan reveals 500 mL urine
B.Serum creatinine 8.5 mg/dL
C.Capillary refill greater than 3 seconds
D.Urine output 30 mL in the last 6 hours
E.Serum potassium 2.8 mmol/L

Answer 115

Answer: B, D
Rationale: Indications of acute kidney injury include elevated serum creatinine and oliguria. Bladder scan reveals urinary retention which indicates the kidneys are still making urine. Capillary refill is not associated with kidney function. Potassium would be elevated, not decreased.
Looking for toxicity to the kidneys - elevated creatinine
Decreased urine output - tells something wrong with kidneys
Bladder scanning - not tell func of kidneys - tell if urinary retention but not tell if kidneys making urine
Cap refill - not deal with kidney func
Serum K - low - kidneys not working see elevated because not excreting like should be