Pharmacology Basics Part 2 Flashcards

(115 cards)

1
Q

Pharmacokinetics

A

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

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2
Q

Pharmacokinetics: 4 processes that are part of it

A

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

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3
Q

Absorption

A

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:

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4
Q

Many factors influence drug absorption: (Absorption)

A

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

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5
Q

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

A

Molecular size, lipid solubility, pH

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6
Q

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

A

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

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7
Q

Oral route

A

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)

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8
Q

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)

A

Must pass through lipoid cell membranes to get to blood stream

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9
Q

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)

A

See metabolism slides

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10
Q

Factors affecting absorption via oral route (Oral route)

A

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)

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11
Q

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

A

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

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12
Q

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

A

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

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13
Q

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

A

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

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14
Q

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

A

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

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15
Q

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

A

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

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16
Q

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

A

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

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17
Q

Gen rules for oral drugs

A

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

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18
Q

Sublingual

A

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

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19
Q

Topical

A

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

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20
Q

Transdermal

A

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

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21
Q

Intravenous (IV)

A

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

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22
Q

Intramuscular (IM)

A

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

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23
Q

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

A

Subcutaneous (SQ)

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24
Q

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

A

Bioavailability

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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: 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
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
Distribution
27
Movement of the drug to body’s tissue (results in therapeutic and adverse effects) (Distribution)
See slides on pharmacodynamics - what drug does to body; how drugs exert their effects
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Lots of these Blood flow to organs/tissues Ability to cross blood-brain barrier or fetal/placental barrier - Drug properties
Factors affecting distribution
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Blood flow to organs/tissues (Factors affecting distribution)
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
30
Ability to cross blood-brain barrier or fetal/placental barrier - (Factors affecting distribution)
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
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Drug properties (Factors affecting distribution)
Affects distribution Protein binding (albumin - protein; most abundant protein in plasma) Water solubility vs. lipid solubility
32
Protein binding (albumin - protein; most abundant protein in plasma) (Drug properties (Factors affecting distribution)
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
33
Chronic liver disease - (Protein binding (albumin - protein; most abundant protein in plasma) (Drug properties (Factors affecting distribution)
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
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Water solubility vs. lipid solubility (Drug properties (Factors affecting distribution)
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
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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:
Metabolism (aka biotransformation)
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Liver is the primary site/organ for metabolizing drugs (Metabolism (aka biotransformation)
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
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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)
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
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Metabolic activity may be decreased in some patients (Metabolism (aka biotransformation)
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
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Nurse: (Metabolism (aka biotransformation)
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
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Enzyme induction Enzyme inhibited
Metabolism: hepatic enzyme sys probs - alter metabolism
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Enzyme induction (Metabolism: hepatic enzyme sys probs - alter metabolism)
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
42
Enzyme inhibited (Metabolism: hepatic enzyme sys probs - alter metabolism)
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
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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
Metabolism: first pass effect (oral route)
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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
Excretion
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Kidney dysfunction (Excretion)
Drugs not excreted effectively; reach toxic levels
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Liver/bowel are secondary site for excretion (Excretion)
Drugs processed by liver, released into bile, eliminated in feces
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
Dynamic equilibrium
48
All 4 processes of pharmacokinetics: lead to a dynamic equilibrium of a drug (Dynamic equilibrium)
Absorption from site of entry Distribution to active site Metabolism in liver Excretion from body
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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
Onset
50
Time for a drug to reach its maximum therapeutic response
Peak
51
Time a drug concentration sufficient to elicit therapeutic response When no longer have impact and therapeutic effect ends then duration of effect ends
Duration
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
Half-life
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Therapeutic MEC = Amount of a drug that is needed to cause a therapeutic effect Loading dose
Pharmacokinetics: minimal effective concentration (MEC)
54
Therapeutic MEC = Amount of a drug that is needed to cause a therapeutic effect (Pharmacokinetics: minimal effective concentration (MEC)
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
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)
Too much drug = toxic (poisonous) effects; likely experience toxicities - sometimes can be life threatening Too little drug = will not produce desired therapeutic effects want
56
Loading dose (Pharmacokinetics: minimal effective concentration (MEC)
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
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Half-life How drug attains and maintains therapeutic range (steady state) Therapeutic window/range/index
Pharmacokinetics: half-life and therapeutic window/range
58
Half-life (Pharmacokinetics: half-life and therapeutic window/range)
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
59
How drug attains and maintains therapeutic range (steady state) (Pharmacokinetics: half-life and therapeutic window/range)
Repeated doses of drug are given Drug accumulates in bloodstream Plateau is reached Amount administered equals amount eliminated
60
Therapeutic window/range/index (Pharmacokinetics: half-life and therapeutic window/range)
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
61
Half-life examples
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
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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
Therapeutic drug monitoring
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Blood test performed to determine levels of drugs (Therapeutic drug monitoring)
Determine therapeutic range and avoid toxicity
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Peak and Trough (Therapeutic drug monitoring)
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
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Tests to determine highest and lowest blood level of drug (Peak and Trough (Therapeutic drug monitoring)
Trough Peak
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Trough (Tests to determine highest and lowest blood level of drug (Peak and Trough (Therapeutic drug monitoring)
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
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Peak (Tests to determine highest and lowest blood level of drug (Peak and Trough (Therapeutic drug monitoring)
Highest level of the drug in the bloodstream drawn 1 hour after infusion completed Timing matters sig - decisions about dose based on draw
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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
Factors influencing drug effects
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Remember (Factors influencing drug effects)
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
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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
Factors influencing drugs effect
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Gender (Factors influencing drugs effect)
Depending on route giving med Men – more vascular muscles; women-more fat cells- slow release
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Physiological Factors (Factors influencing drugs effect)
Diff drugs acts diff Hydration (dehydration), acid-base, electrolytes
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Pathological Factors (Factors influencing drugs effect)
Disorders change conditions for drug (vascular, GI, liver, kidney disease, etc.)
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Genetic Factors (Factors influencing drugs effect)
Lack enzymes, cultural differences
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Psychological Factors (Factors influencing drugs effect)
Attitude: placebo effect, trust in HCP
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Environmental Factors (Factors influencing drugs effect)
Temperature, exercise, relaxed environment
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Tolerance (Factors influencing drugs effect)
Larger dose needed
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Interactions (Factors influencing drugs effect)
Two or more drugs
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Happen Any part pharmokinetic process and impact any drug Site of absorption During distribution/site of action During metabolism During excretion
Drug-drug interactions: altered effectiveness
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Site of absorption (Drug-drug interactions: altered effectiveness)
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
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During distribution/site of action (Drug-drug interactions: altered effectiveness)
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
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During metabolism (Drug-drug interactions: altered effectiveness)
One drug stimulates or blocks metabolism of another drug Hepatic enzyme sys - 2 drugs together can alter enzyme sys
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During excretion (Drug-drug interactions: altered effectiveness)
One drug competes for other to be excreted-leads to accumulation/toxicity
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Prevent absorption (with the oral route) Increase or decrease drug's effect (any route)
Drug-food interactions
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Prevent absorption (with the oral route) (Drug-food interactions)
Increased acid production- speeds breakdown of drug Milk products: calcium binds to drugs, decreased absorption; come up a lot Chemical reaction
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Chemical reaction (Prevent absorption (with the oral route) (Drug-food interactions)
Ex: Iron and Ca binds with tetracycline - avoid taking products with Iron/Ca because not absorb it and not have effect want to have
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Increase or decrease drug's effect (Drug-food interactions)
Food affects liver enzymes actions
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Food affects liver enzymes actions (Increase or decrease drug's effect (Drug-food interactions)
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
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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
Adverse effects
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Types of adverse effects/rxns (Adverse effects)
Primary Actions/adverse effects Secondary Actions/adverse effect Toxicity Allergic reactions
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Primary Actions/adverse effects (Types of adverse effects/rxns (Adverse effects)
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
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Secondary Actions/adverse effect (Types of adverse effects/rxns (Adverse effects)
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
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Adverse effects: EX (Adverse effects)
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
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Auditory damage (Adverse effects: EX (Adverse effects))
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
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Headache (Adverse effects: EX (Adverse effects))
Related to action and dose-dependent; anti-hypertensives - vasodilation Related to increased intracranial pressure Idiosyncratic - lot times just happen Many drugs cause headaches Withdrawal
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Adverse effects: Toxic effects to organs (Adverse effects)
Organs most likely to suffer toxicity with meds Liver Kidney Nervous system
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Liver (Adverse effects: Toxic effects to organs (Adverse effects)
CM: Fever, nausea, jaundice, urine dark orange or clay stool Labs: elevated liver enzymes, PTT (bleeding time)
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Kidney (Adverse effects: Toxic effects to organs (Adverse effects)
CM: change urinary pattern (oliguria) - stop urinating when go to AKI Labs: elevation BUN and creatinine
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Nervous system (Adverse effects: Toxic effects to organs (Adverse effects)
CM: looking at mainly Change behavior, looking at mainly level of consciousness, cognition
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Adverse rxns: allergic rxns (Adverse effects)
2 most common allergic rxns seen with meds Anaphylaxis Delayed Allergic Reaction
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Anaphylaxis (Adverse rxns: allergic rxns (Adverse effects)
Massive histamine release Involves massive systematic response (histamine) Clinical manifestations:
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Involves massive systematic response (histamine) (Anaphylaxis (Adverse rxns: allergic rxns (Adverse effects)
Leads to bronchoconstriction, shock, and death
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Clinical manifestations: (Anaphylaxis (Adverse rxns: allergic rxns (Adverse effects)
Hypotension, tachycardia, dyspnea, edema, hives, itching, respiratory or cardiac arrest
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Delayed Allergic Reaction (Adverse rxns: allergic rxns (Adverse effects)
Occurs hours to days after exposure/take med Clinical manifestations Not place where full blown anaphylaxis - localized to skin and joints
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Clinical manifestations (Delayed Allergic Reaction (Adverse rxns: allergic rxns (Adverse effects)
Diffuse Rash all over skin, hives, itching, swollen joints
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Penicillin allergy (Adverse effects)
Developed delayed allergic rxn
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Angioedema (Adverse effects)
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
108
Stevens Johnson Syndrome (Adverse effects)
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
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Extension of Stevens Johnson Syndrome (Stevens Johnson Syndrome (Adverse effects)
Toxic epidermal necrolysis (TENS) - rxn to drugs; another serious but rare
110
Allergic Rxns: nursing interventions (Adverse effects)
Need know what do First: Next: - stopped admin and put O2 on them if having difficulty breathing
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First: (Allergic Rxns: nursing interventions (Adverse effects)
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
112
Next: - stopped admin and put O2 on them if having difficulty breathing (Allergic Rxns: nursing interventions (Adverse effects)
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
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: 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.
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: 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
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: 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