Module 1 Flashcards
Pharmacokinetics
movement of drug through body (what body does to the drug)
absorption, distribution, metabolism, excretion
MEC, steady state, duration of action
Pharmacodynamics
study of the effects of the drug (what drug does to the body)
receptor binding, post receptor effects, chemical reaction
Minimum Effective Concentration (MEC)
the minimum amount of drug required to work (to produce intended effect)
Absorption
movement of drug into the bloodstream
• passive transport (diffusion, facilitated diffusion)
• active transport (requires energy and enzyme)
• pinocytosis (cell carries drug across membrane by engulfing drug particles)
factors affecting absorption are blood circulation, pain, stress, food texture/fat content/temp, pH, route of administration
First Pass Effect (Absorption)
how much of the drug is metabolized in liver after passing through GI tract via hepatic vein
ingestion, absorption into small intestine, portal circulation through portal vein to liver, metabolism, reduced bioavailability with PO MEDS
Bioavailability
percentage of drug in the bloodstream after first pass effect
IV push= 100%
Distribution
distribution of the drug into the tissues
the drug is exiting the vascular system and being deposited to the tissues
consider transfer through capillary beds, placenta, blood brain barrier (BBB) aka permeability of cell membrane and circulation, etc.
protein binding (albumin)
Metabolism (Biotransformation)
how the body chemically modifies drugs into what can be excreted (P40 liver system)
consider liver function because it’s the main metabolism organ; liver lab values as well as age (infants and elderly)
therapeutic consequences: accelerated renal drug exertion, increased therapeutic action, activation of prodrugs, increased/decreased toxicity
Excretion
removal of the drug from the body (GI, kidneys, lungs, breast milk, saliva, hair, sweat, bile)
consider kidney function because it’s the main excretion organ; GFR, creatinine, BUN
first pass loss, half life
Half-Life
the time it takes for half the drug to be eliminated
if a drug has a short half life, that means it leaves the body quickly/higher risk of dependency and lower risk for toxicity…long half life means it leaves the body slowly/lower risk for dependency and higher risk for toxicity…CONSIDER DOSING
single dose time course determined by metabolism and excretion, repeated doses to achieve plateau drug lvls (takes time to plateau); LOADING DOSE VS MAINTENANCE DOSE
Therapeutic Index (TI)
a way to monitor the concentration of certain drugs is through obtaining a peak (highest concentration of drug in blood; most active) and a trough (lowest concentration of drug in blood; usually measured before next dose) level (”titers”, “serum drug levels”)
RATIO BETWEEN MTC AND MEC
some drugs have a narrow TI and need close monitoring of these lvls, high TI means drug is safer
Onset
when drug starts to have effects
Peak
what time is highest concentration of drug in bloodstream
Duration
how long drug effects lasts (therapeutic effects)
Receptor Theory
the proteins bind to receptors and tell the cells to activate or inactivate to produce or block a response
Agonist
turns on receptors
partial agonist lower affect than full agonist
Antagonist
blocks receptors
non-receptor responses: no use receptors
Non-Specific
one type of receptor at multiple sites
Non-Selective
multiple types of receptors anywhere in the body
Pharmacogenetics
the study of genetic factors influencing individual drug response
Focus of Pharmacogenetic Testing
look at specific DNA segments that play a role in the body’s response to a drug
Benefits of Pharmacogenetic Testing
- individualized treatment regimen
- decreases drug reactions and treatment failures
- promotes drug adherence
- reduces healthcare costs
- improve quality outcomes
- predict pt response to drug therapy
Interpatient Variability in Drug Responses (Pharmacodynamics)
measurement of inpatient variability; the ED50 vs LD50 (TI is ratio between these and can overlap between the curve for what is effective and what is lethal)
Additive
sum of effects of 2 drugs; increased effects
Synergistic
effect is much greater than effects of either drug alone
Antagonistic
one drug reduces/blocks effect of other drug
Drug-Nutrient Interactions
food may increase, decrease or delay drug response
Drug-Lab Interactions
drugs may cause misinterpretations of test results
Drug-induced photosensitivity
skin reaction caused by sunlight exposure
Pharmacogenomics
study of combo of pharmacology and genomics to develop effective and safe meds to compensate for genetic differences in pts that cause varied responses to a single therapeutic regimen
Who benefits from pharmacogenetics?
those taking multiple prescription drugs
those not responding to current therapy
those having adverse drug reactions
those taking black box warning drugs
Toxicity
identified by monitoring the plasma (serum) therapeutic range of the drug
drug level exceeds TI- toxic effects are likely to occur from overdosing or drug accumulation
Pregnant Clients
• MUST REPORT ALL MEDS TAKEN BECAUSE THEY ALL HAVE POTENTIAL RISK! (begin as early as 2 weeks after conception)
• HEALTH OF FETUS RELIES ON HEALTH OF MOTHER SO MEDS MAY BE NECESSARY; PT EDUCATION!!
ABCDX Categories
A= smallest risk
B= slight risk
X= WORST RISK; TERATOGENIC EFFECT CONFIRMED; DO NOT USE: BACK UP BIRTH CONTROL
Pediatric Clients
• family centered care and should include safe med administration and pt teaching
• atraumatic care
• cognitive/affective/psychomotor skills
USE SMALLEST SYRINGE SIZE TO INCREASE ACCURACY OF DOSE GIVEN
MAINTAINING SAFETY WITH MINIMAL RESTRAINT; DISTRACTION AND OTHER NONPHARM FOR PAIN AND ANXIETY
Pediatric Dosing
different due to immature hepatic and renal function; meds are WEIGHT BASED
USE SMALLEST SYRINGE SIZE TO INCREASE ACCURACY OF DOSE GIVEN
Atraumatic Care
means to decrease psychological/physical distress; do NOT separate pediatric pts from caregivers
Older Adult Clients
• goal is to PROMOTE AUTONOMY, keep them independent
• polypharmacy
• expect that older adults CAN learn
• may need help with adherence (write down when meds are taken, use an app, etc.)
• determine if sensory/cognitive barriers exist
• toxicity and overdose may present as CONFUSION
• may see alterations in dosing due to aging organs/chronic illnesses; ESPECIALLY IN PTS WITH GI, KIDNEY, LIVER, OR CARDIAC
MONITOR FOR KIDNEY (BUN/CREATININE) AND LIVER (AST/ALT)
Polypharmacy
5+ meds; increases risk for drug interactions and side effects
Basic Considerations of Drug Therapy During Pregnancy
health of fetus depends on health of mother
physiological changes during pregnancy
placental drug transfer
adverse effects
Drug Therapy During Breast Feeding
dose immediately after
avoid drugs that have a long half life
choose drugs that tend to be excluded from milk
choose drugs least likely to affect infant
avoid drugs that are known to be hazardous
Absorption Influencing Factors for Pediatrics
child’s age, health status, weight, route of administration
nutritional habits, physical maturity, hormonal differences
hydration, underlying disease, GI disorders
Route of Administration for Pediatrics
gastric acidity
emptying
motility
surface area
enzyme levels
intestinal flora
IM/SQ: peripheral effusion, effectiveness of circulation
Topical: children’s skin is thin and porous
Distribution Influencing Factors for Pediatrics
body fluid composition (75% water)
body tissue composition (less body fat)
protein-binding capability (less albumin and fewer protein receptor sites)
effectiveness of barriers (skin, BBB)
Metabolism Influencing Factors for Pediatrics
maturational lvl of child
liver metabolism
reduced hepatic blood flow and drug metabolizing enzymes
higher metabolic rate
Excretion Influencing Factors for Pediatrics
kidneys (infants have decreased renal blood flow, GFR, renal tubular function)
intestines, salivary glands
lungs
sweat glands, mammary glands
Adolescent Considerations
specific to developmental stage
physical changes
cognitive lvl and abilities
emotional factors
impact of chronic illness
self care abilities
social reasoning and decision making
Family Centered Assessment
age, weight, height
developmental age
health status
history of drug use
nutritional/hydration status
cognitive level
family/child understanding
Family Centered Planning
child and caregivers will…
recognize need for drug administration
incorporate drug treatment regimen into lifestyle
demonstrate safe drug administration practices
child receives dose based on assessment data consistent with guidelines
Family Centered Interventions
• assist pt, family and caregivers to use appropriate follow up resources and support
• follow all rights of safe drug administration
• help pt, family and caregivers to manage complex drug schedules
• use educational strategies that are interactive and engaging for pediatric pt
• pt teaching
Family Centered Patient Teaching
report use of OTC products
report side effects immediately
advise breastfeeding pt that a portion of most drugs is excreted in breast milk
keep meds out of reach for children
use child resistant containers
Family Centered Evaluation
• determine family members knowledge concerning drug, dose, schedule for administration, and side effects
• determine child’s physiologic and psychological response
• determine therapeutic and adverse effects of drugs
• help pt, family and caregivers to manage complex drug schedules
• use educational strategies that are interactive and engaging for pediatric pt
Older Adult Absorption
delayed gastric emptying; decreased gastric acidity and decreased splanchic blood flow
Older Adult Distribution
higher % of fat; decreased lean muscles, total body water and plasma albumin concentration
Older Adult Metabolism
decreased rate of liver metabolism of drugs and activity of liver enzymes
can raise half lives of some meds
Older Adult Excretion
reduced renal excretion (decreased GFR and # of nephrons)
creatinine clearance more accurate than serum creatinine
Geriatric Pharmocodynamics
• age related changes in CNS and cardiovascular system
• changes in # of drug receptors
• changes in affinity of receptors to drugs
• compensatory response to physiologic changes is decreased
• decreased responsiveness and sensitivity to baroreceptors
• changes in vision, hearing, endurance/mobility and skin
Physiological Changes Associated with Diseases in Older Adults
cardiac (impaired CO, greater susceptibility to cardiac adverse effects)
kidney and liver disease
neurological (impaired cerebral blood flow, greater sensitivity to neurological effects of meds, diminished neurotransmitter lvls)
Geriatric ADEs
stimulate stereotypes of growing old
falls from orthostatic hypotension
confusion and disorientation
nervousness
incontinence
malaise
Medications Contributing to ADEs in Older Adults
cardiovascular
psychotropic meds
anti diabetic agents
antibiotics
anticoagulants
NSAIDs
Older Adult Drug Adherence
pt may not fully understand drug regimen
nonadherence can cause under/overdosing
barriers to effective drug use; MED EDUCATION IS IMPORTANT!!
Health Teaching: Special Considerations
• have pts senses be sharp (clean eyeglasses, functional hearing aids in place)
• speak in tones pt can hear
• face pt when speaking
• treat pt with respect; EXCEPT PT CAN LEARN
• use large print and bright colors when teaching
• review all meds at each visit
• encourages simple dosing schedule
• w/onset of confusion/disorientation, suspect recent prescribed meds
• encourage pt to report if new drug isn’t improving condition for which it was prescribed for
PNS (Urinary Retention and HTN)
mediates detrusor muscle contraction; blocked by anticholinergic meds like diphenhydramine
SNS (Urinary Retention and HTN)
alpha adrenergic activity causes urethral sphincter to contract (retaining urine)
alpha adrenergic activity increases systemic vascular resistance (raises BP)
decongestants are alpha adrenergic agonists (pseudoephedrine and phenylephrine)
Orthostatic Hypotension and Hip Fracture
alpha adrenergic blockage can worsen postural hypotension and increase risk of falls
falls and hip fractures are associated with significant morbidity and mortality in older adults
Drug Induced Delirium
meperidine- synthetic opioid (can cause confusion, activate metabolites and slow renal clearance in older adults)
diazepam- long acting benzodiazepine (extended half life in elderly, increased sensitivity in elderly and risk of falls/fractures)
Beers Criteria
consensus based list of potentially inappropriate meds for older adults
Antihistamines (Upper Respiratory)
H1 Receptor Antagonists
1st gen (diphenhydramine-Benadryl)
2nd gen (cetirizine- Zyrtec)
ANYTHING THAT ENDS IN -INE!!!
compete with histamine for receptor sites and prevent histamine response; relieves allergic reactions
consider safety with CNS depressants; consider age when administering, as older adults may be more sensitive to SE and children may have paradoxical effects
Antihistamines SE
DROWSINESS (1st gen more severe)
dry mouth
urinary retention ANTICHOLINERGIC
constipation
blurred vision
excitation (paradoxical effect in children)
CANT SEE CANT PEE CANT SPIT CANT SHIT
monitor dosing in older adults d/t impairment of organs; more sensitive to SE
Decongestants/Alpha Adrenergic Agonist (Upper Respiratory)
oxymetazoline (Afrin)
reduce swelling within blood vessels of nasal cavity and decreases secretion; stimulate SNS producing vascular constriction of capillaries within nasal mucosa which shrinks membranes and reduced fluid secretion
relives nasal/sinus congestion and decreases sinus pressure and decrease pain
sprays and drops preferred; oral form will cause systemic side effects
meds such as ephedrine, phenylephrine, pseudoephedrine (Alpha Adrenergic Agonists) may also be used for decongestant properties
Decongestants SE
nervousness/restlessness/palpitations
headache
dry mouth
nasal irritation (depending on route)
increased BP and glucose
REBOUND NASAL CONGESTION IF PROLONGED USE (AVOID USE GREATER THAN 3 DAYS)
Intranasal Corticosteroids (Upper Respiratory)
fluticasone (Flonase)
ENDS IN -SONE
reduces nasal inflammation and congestion (blocks inflammatory responses) may take 1-4 weeks to reach full effect
beneficial in treating rhinitis; should be used for short term only
Intranasal Corticosteroids SE
dizziness
hoarseness (vocal cord irritation)
blurred vision
nausea/vomiting
increased nasal secretions
Antitussives (Upper Respiratory)
dextromethorphan (Robitussin DM)
reduce cough by blocking the cough reflex in medulla (cough control center); SE IS NAUSEA, dizziness and CNS suppression at high doses
used for non productive cough ONLY unless needed to sleep; contraindicated for pts with COPD
short term use only; no alcohol or CNS depressants; get up slowly to avoid falls
opioids may be used for severe cough
Upper Respiratory Medications
• may need to educated on potential side/adverse effects of OTC meds since pts use w/o supervisor
• combining these drugs may lead to harmful effects due to some meds having similar drug components
• pts should ALWAYS be asked separately about OTC meds
Sympathomimetics/Bronchodilators (Lower Respiratory)
Short Acting Beta2-Adrenergic Agonists (SABAs) and Long-Acting Beta2 Agonists (LABAs)
-TEROL!!
short acting (albuterol (Ventolin)- RESCUE)
long acting (salmeterol (Severent)) for COPD AND ASTHMA; NOT A RESCUE!!
bronchodilation!!!
ALBUTEROL IS FOR ACUTE ASTHMA ATTACKS; SALMETEROL JS FOR SLOW AND STEADY
how often are they using it? using too much might reverse intended effects or indicate poor asthma control, rebound bronchoconstriction; excessive dosage can cause heart attacks or seizures
Sympathomimetics SE
increased SNS s/s like pre-workout
increased HR/palpitations/arrhythmias, chest pain
nervousness
tremor
increased energy/anxiety
Anticholinergics (Lower Respiratory)
tioptropium (Spiriva)
-TROPIUM!!
treatment of bronchospasms; blocks acetylcholine receptors (PNS) reducing frequency of bronchospasms in COPD and asthma
capsule of Dry Powder is used in inhaler
keep capsule in package until ready to use
Long acting: THIS DRUG IS NOT TO BE USED AS RESCUE INHALER!!!
Anticholinergics SE
blurred vision (contraindicated in narrow angle glaucoma; increases intraocular pressure)
headache
rash
dry mouth
constipation
urinary retention
n/v and indigestion
peripheral edema (aldosterone)
insomnia (increases SNS)
oral ulceration (mucous membrane irritation)
CANT SEE CANT PEE CANT SPIT CANT SHIT
Leukotriene Inhibitors (Lower Respiratory)
montelukast (Singulair)
-LUKAST!!
decreased acute asthma attacks and exercise induced bronchoconstriction (good for kids depending on lvl of activity); reduces inflammatory processes by decreasing effect of leukotrienes; PREVENTION ONLY!!!
given PO: take tablet 2 hrs before exercise; AVOID USE WITH NSAIDS CAUSE IT BLOCKS DRUG ACTION
NOT TO BE USED AS RESCUE MED!!
Leukotriene Inhibitors SE and ADE
SE: GI upset, fatigue, neuro disturbances (dizziness/confusion), HA, immunosuppression, angioedema, bleeding
ADE: Steven Johnson’s Syndrome (SJS), suicidal ideation
Steroids/Glucocorticoids (Lower Respiratory)
beclomethasone (Beconase)
anti-inflammatory (use for moderate-severe exacerbations) may take 1-4 weeks to reach full effect
likely to cause fungal infection if inhaled; consider pt teaching (rinse mouth, spacer use, proper storage)
MUST TAKE DAILY AS PRESCRIBED TO SEE THERAPEUTIC EFFECTS; USE SPACER
Steroids/Glucocorticoids SE
headache
dry mouth/throat irritation/oral thrush
dysphonia (hoarseness)
adrenal suppression (in high dose long term use only)
Lower Respiratory Meds
• asthma can be a complicated illness to treat; good pt education is crucial for control (help pt identify triggers of asthma to reduce frequency of attacks)
• consider pt teaching for respirator drug therapy (how to use inhaler and how to store)
• inhaled meds work more quickly than oral, and use of spacers allows for meds to reach target areas for effectively
• increased use of rescue inhaler (albuterol aka Ventolin) can indicate poor control of asthma symptoms; report need of increased use to provide as a step up in drug therapy may be required
Chemical Name
exact scientific name that describes the chemical structure of a drug
generic name (NON PROPRIETARY)
official name of the drug, usually simpler than chemical name used by everyone
Trade name (PROPRIETARY)
brand name that a drug is sold under; chosen by manufacturer
Prototype
serves as the model drug for the class (STUDY THESE!! ITLL HELP FOR OTHER DRUGS OF THE SAME DRUG CLASS)
Therapeutic Classification
tells you WHAT the drug does for the body
Pharmacologic Classification
tells you HOW the drug works in the body (mechanism of action)
Oral Meds
slowest absorption time
IM Absorption
rate of absorption depends on blood perfusion level
MTC (Minimum Toxic Concentration)
smallest amount of drug that can cause harm/SE; dose at which drug starts becoming dangerous
Loading Dose
high initial dose to achieve quick therapeutic response
Rhinitis
inflammation and swelling of the mucous membranes in the nose; triggered by release of histamine which causes mucous membranes of the nose and pharynx to swell and increase secretion production
ANTIHISTAMINES AND CORTICOSTEROIDS
Sinusitis
an infection or inflammation of the lining of the sinuses (air filled pockets that become filled with fluid)
DECONGESTANTS
Common Cold
viral infection of upper respiratory tract
ANTITUSSIVES
Antihistamines Safety and Contraindications
avoid drinking and CNS depressants/operating heavy machinery
narrow angle glaucoma (increases intraocular pressure, causing fluid build up)
Antihistamines Nursing Care
• give oral meds w/food; monitor I and O
• suck on ice chips or sugarless candy to help with dry mouth
Decongestants Contraindications
HYPERTENSION, coronary artery disease
Decongestants Nursing Care
MONITOR HR, BP AND BG
be aware of interactions w/caffeine and stimulants, MAOIs and beta blockers
Corticosteroids Nursing Care
• intranasal preferred to prevent systemic side effects
• inhaled=long term prophylaxis of asthma (taken daily!) NOT FOR ACUTE ATTACK
• IV/Oral= short term therapy of severe, acute asthma (TAPER OFF!!! USE FOR LESS THAN 10 DAYS)
• RINSE MOUTH WITH WATER TO AVOID ORAL THRUSH
• watch for s/s of infection (suppressed immune system) and BG
• KNOW TRIGGERS!
The S’s of Steroids (Systemic SE)
• Soft bones (increase r/f osteoporosis; decreases Ca absorption)
• Sight (increase r/f cataracts)
• Slimy tongue (thrush-USE SPACER AND RINSE)
• Sugar (hyperglycemia)
• Sickness (suppresses immune system, increase r/f infection)
• Salt (increases aldosterone-fluid/salt retention)
SABAs/LABAs Nursing Care
• monitor vitals (HR, RR)
• assess breath sounds (wheeze to no wheeze?)
• encourage hydration (thins mucus)
• assess # of times SABAs is used
• PEAK FLOW METER TO ASSESS ASTHMA CONTROL
• use SABA before ICS; WAIT 5 MIN TO ALLOW AIRWAYS TO BE OPEN ENOUGH
• wear medic alert tag and carry rescue inhaler
Anticholinergic ADE
cardiac dysrhythmias
anaphylaxis
hyperglycemia (cortisol)
depression
Anticholinergic Nursing Care
• MONITOR VITALS (HR, BP, RR) and I/Os
• encourage hydration to thin mucus (2-3 L)
• keep capsule in package until ready to use
• suck on ice chips or sugarless candy
• rinse mouth to reduce dry mouth and irritation with DPI
• proper technique
Leukotriene Inhibitors Nursing Care
avoid use of NSAIDs
monitor behavior and signs of worsening depresssion
take once daily at bedtime (if not taken daily, take meds 2 hrs before exercise)
