Intro to pharmacology Flashcards
1
Q
Definition of drug
A
- any substance taken by mouth, injection to muscle, blood vessel, cavity of body; inhaled, or applied topically to treat or prevent disease or condition
- restoring, correcting or modifying organic functions in man or animal
- drugs do not confer any new properties on cells/ tissues
2
Q
Drug actions which are achieved by biochemical interactions b/w the drug and certain tissue components in the body (receptors) are divided into what 2 classes
A
- Pharmacokinetic interactions (how the body handles the drug)
- Pharmacodynamic interactions ( the drug’s effect on the body)
3
Q
What is CPS
A
COMPENDIUM OF PHARMACEUTICALS AND SPECIALTIES
= a frequently updated list of every drug in the world
4
Q
What is Pharmacology
A
the study of drugs and their effects on living organisms
5
Q
what is pharmacokinetics
A
the processes which determine the concentration of a drug in the body over time; method drug enters body, moves around, breaks down and is eliminated. includes: -absorption -distribution -biotransformation -elimination
6
Q
What is pharmacodynamics
A
the study of the actions of drugs on living tissues (cellular level)
- study of how drug acts on living organism
- drugs can only alter the functions of tissues, cannot cause a new function
7
Q
What is Pharmacognosy
A
the study of natural drug sources
8
Q
Define untoward effects
A
- the undesired effects that a drug has on the body
- a side effect that proves harmful to the pt
9
Q
Define side effect
A
-unavoidable, undesired effects frequently seen even in therapeutic drug dosages
10
Q
define orphan drugs
A
used specifically to treat a rare disease
-expensive drugs as not many ppl need them
11
Q
Define indication
A
- medical condition or conditions in which the drug has proven to be of therapeutic value
- presenting sx and or hx that supports the decision to administer a drug
12
Q
define contraindications
A
-presenting sx and or hx that negate the decision to administer a drug
= Do not give drug if pt has these
13
Q
Define agonist drug
A
- drug or substance that binds w/ specific drug receptor & causes a physiological response
- drugs which bind to receptor sites and produce a cellular reaction
14
Q
Define antagonist drugs
A
- the opposition btw 2 or more drugs
- a drug or other substance that blocks a physiological response or that blocks the action of another drug or substance
- a blocking agent, prevents other substances from producing an effect
- drug which binds to a receptor but produces no reaction
(ex. narcan reverses opiod od)
15
Q
Can drugs be both agonist and antagonist
A
yes
16
Q
Define efficacy
A
- power of drug to produce therapeutic effect
- drugs ability to initiate biological activity once bound
- differs btw ppl
17
Q
Define affinity
A
-the tendency of a drug to combine w/ a specific drug receptor
18
Q
define bolus
A
single, often times large dose of medication
19
Q
define cumulative action
A
- a drug is administered in several doses, causing an increase effect usually due to the quantitative buildup of the drug in the blood
- toxic effects from repeated doses prior to adequate elimination from the body
20
Q
Define depressant drug
A
-medication that decreases or lessens a body function or activity
21
Q
Define habituation
A
- physical or psychological dependence on a drug
- process of becoming accustomed to a drug due to frequent use
- tolerance and dependence develop
- drug is no longer taken for therapeutic effects but rather to avoid unwanted effects of not taking the drug
22
Q
Define drug dependence
A
- condition in which a person cannot control drug intake
- may be physiological, psychological, or both
23
Q
Define hypersensitivity
A
- reaction to a substance that is more profound than seen in a population not sensitive to the substance
- allergic reaction
24
Q
Define Idiosyncrasy
A
-individual reaction to a drug that is unusually different from that seen in the rest of the population
25
Define Potentiation
- increased or enhanced action of 2 drugs where total effect is greater than the sum of independent effects (1 + 1=4)
- one drug intensifies the other
ex: barbiturates and ETOH
26
Define refractory
- pts of conditions that do not respond to a drug are said to be refractory to that drug
ex: pt w/ VC that does not respond to lidocaine
27
Define Stimulant
-drug that enhances or increases a bodily function
28
Define synergism
- combined action of 2 drugs
- joint actions of 2 drugs to produce an effect neither one could alone
- the action is much stronger than the effects of either drug administered separately
ex: caffeine increases duration of analgesic effects of acetaminophen, NSAID's and opioids
29
Define therapeutic action
-desired, intended action of a drug given in the appropriate medical condition
30
Define therapeutic dose (range)
-range of plasma concentration of a drug that produces the desired effects w/o producing lethal toxic effects
31
Define therapeutic threshold
-minimum effective concentration of a drug necessary to cause the desired response
32
therapeutic index
- difference between minimum effective concentration and toxic dose
- different w/ each drug
33
Define tolerance
-when pts are receiving drugs on a long-term basis, they may require larger and larger dosages of the rug to achieve therapeutic effect
34
Define onset of action
-interval btw the time a drug is administered and the first signs of effects
35
Define duration of action
-length of time that the plasma concentration stays above the minimum effective level for a therapeutic response
36
Define peak concentration
-highest plasma concentration achieved from a dose
37
define toxic dose
-plasma concentration at which a drug produces serious side effects
38
define relative potency
-relative amount of a drug required to produce the desired response
39
define half-life
- time required for body to fully eliminate 50% of a drug
- determines the frequency of dosing\
- takes 5-6 half lives for a drug to be eliminated
40
define summation
-aka additive effect, two drugs with the same effect are given together (~1+1=2)
41
Define tachyphylaxis
-quickly developing tolerance following repeat administration over short period of time
42
Define drug interaction
-effects of one drug alter the response to another drug
43
Define chemical name
-specifies the chemical structure of the drug
44
Define generic name
- nonproprietary name / does not belong to a particular company
- standard name assigned by national agency
- most commonly used
45
Define trade name
- brand or proprietary name
- name and registered trade mark a drug manufacturer gives to a drug
- always capitalized
46
Define official name
- usually same as generic followed by USP or NF
| - used in official publications listing drugs conforming to standards
47
what are 6 things on drug label
- trade name
- generic name
- date dispensed
- doctor prescribed Rx
- dosage
- # of doses
48
what are 4 sources of drugs
- plants
- animals
- minerals
- laboratory (synthetic)
49
what are 4 components taken from plants to make drugs
- alkaloid
- glycosides
- gums
- oils
50
why are alkaloids the most important component
- react w/ acids to form salt
- salt is more readily soluble in body fluids
- usually end in -ine as in atropine, caffeine, nicotine
51
5 examples of plant derivative drugs
```
Opium plant:
-morphine
-heroine
-codeine
Atropa belladonna
-Atropine
Purple foxglove
-digoxin
```
52
What is used when sourcing from animal and humans
body fluids or glands
| -hormones, fats, oils & enzymes that act as catalysts
53
What source are vaccines from
animals
54
4 examples of animal derivative drugs
- insulin
- oxytocin
- cod liver oil
- pepsin
55
What are minerals or mineral products as sources for drug
- metallic and nonmetallic minerals provide various inorganic material not available from plants or animals
- mineral sources are used either alone or combined w/ other ingredients to yield acids, bases or salts
56
3 examples of mineral derivative drugs
- sodium bicarbonate
- calcium chloride
- magnesium sulfate
57
What are synthetic sources of drugs
- chem substances made in lab
- result of advancements in tech
- allows to produce greater quantities & develop safer drugs (less adverse reactions)
58
3 examples of synthetic dugs
- Lidocaine (xylocaine)
- Diazepam (Valium)
- Human insulin (Humulin)
59
11 components of a drug profile
- name
- classification
- mechanism of action
- indications
- pharmacokinetics
- side effects
- routes of administration
- contraindications
- dosage
- how supplied
- special considerations
60
What is classification of a drug
-broad group to which a drug belongs. knowing classifications is essential to understanding the properties of drugs
61
define mechanism of action
-the way in which a drug causes its effects; its pharmacodynamics
62
define dosage
amount of the drug that should be given
63
define supplied
Typically includes the common concentration of the available preparations; many drugs come in diff concentrations
64
define special conciderations
how drug may affect pediatric, geriatric or pregnant pts
65
What is Base Hospital Direction
- a BHP certifies medics to perform delegated acts (symptom relief)
- acts done under physicians license (medical director)
- medics cannot deliver drugs off duty; nor act under another MD license
- medic can be decertified if fail to follow guidelines
66
How to provide safe and effective Pt care
- know precautions, contraindications for all meds you give
- proper technique
- observe and document drug effects
- have current knowledge in pharmacology
- professional relationships with other healthcare providers
- understand pharmacokinetics and pharmacodynamics
- have current med references available
- take careful drug Hx
- evaluate compliance, dosage, adverse reactions
- consult with med direction as needed
67
10 steps to administering medications
1. ID any allergies
2. determine if order is consistent w/ training and scope of practice
3. take and record vitals
4. confirm order (med, dose, concentration, route)
5. select and confirm med
6. confirm med and order w/ partner
7. check for cloudiness, particles, discoloration, expiry date
8. 8 rights
9. record drug, dose, route, time of admin
10. properly dispose of sharps
68
8 Rights of med admin
Right:
- patient
- drug
- dose
- route
- time
- expiry date
- documentation
- to refuse
69
4 types of Pt's for special considerations
- pregnant
- pediatric
- geriatric
- body mass
70
Special considerations with pregnant pts
- some drugs have adverse effect on fetus
- Teratogenic drug can deform or kill fetus
- drug given to mom reaches fetus and may affect breastfeeding baby
71
Anatomical and physiological changes in pregnant mother
```
Increased:
CO
HR
Blood volume
Decreased:
protein binding
hepatic metabolism
BP
```
72
What is Placental barrier
- membrane layers that separate the blood vessels of the mother and fetus
- provides some protection to the fetus
73
What is Broselow Pediatric Emergency Tape
- used for size and drug calculations in infants
- placed along childs length to give a weight
- coded dosage charts and sizes for procedures
74
Pediatric weight formula
(age x 2) + 10
75
Considerations with pediatric patients
- higher proportion of water
- lower plasma protein levels (more available drug)
- immature liver/ kidneys (liver often metabolizes more slowly, kidneys may excrete more slowly)
76
Physiological effects of aging (geriatric pts)
```
Decreased:
CO
renal function (excretion)
brain mass
total body H2O
serum albumin (protein binding)
resp capacity
GI motility
liver function->biotransformation->delayed drug action
Increased:
body fat
```
77
Considerations with geriatric patients
- chronic disease states
- decreased plasma protein binding
- slower metabolism
- slower excretion
- dietary deficiencies
- use of multiple meds
- lack of compliance
78
Consideration Re: Age, weight, gender
```
Age:
immature or decreased hepatic, renal function
Weight:
bigger spread over larger volume
Gender:
diff sizes
diff in fat/water distribution
```
79
Other considerations
- environment
- fever
- shock
- genetic effects
- psychological factors
80
Pathology considerations
- Drug may aggravate underlying pathology
- Hepatic disease may slow drug metabolism
- Renal disease may slow drug elimination
- Acid/base abnormalities may change drug absorption or elimination
81
What do pharmacokinetics depend on
- body's various physiological mechanisms to move substances across the body's compartments
- can be through active or passive processes (mostly passive / diffusion or osmosis)
82
how does insulin facilitate the transport of glucose into the cell
carrier mediated diffusion or facilitated diffusion
83
What are the 5 steps in pharmacokinetic processes
- liberation
- absorption
- distribution
- biotransformation (metabolism)
- excretion
84
What is the absorption process
-a drug must find its way to the site of action via circulatory fluids (passive diffusion)
85
what is distribution process
-drug must be distributed throughout body
86
what is biotransformation process
-process of breaking down, or metabolizing, drugs
87
what is elimination process
- drugs must eventually be excrete from body
| - usually via kidneys but also GI, sweat, saliva and breast milk
88
What is Liberation
-applies to drugs given orally
1. release of drug from pill, tablet, capsule
2. Dissolving of active drug in GI fluids
89
What are formulation factors that affect liberation / absorption
- tablet disintegration
- inert ingredient / solvent effects (coated to slow)
- solubility
- drug pH (acidic drug absorb faster)
- concentration
90
What are patient factors that affect liberation/ absorption
- absorbing surface
- blood flow
- environmental pH
- Disease states (shock, acidosis, peripheral vasoconstriction)
- interactions w/ food or other drugs
91
what is absorption rate of PO and transdermal drugs
~30 - 60 min
92
What is the rate of absorption of SL (sublingual), Vag (vaginal) and PR (rectal)
~15 - 30 min
93
What is absorption rate of topical drugs
~ 60 min
94
what is absorption rate of inhalation drugs and IV (intravenous)
~ 1 min
95
What is absorption rate of SC, IM and IO
~Several mins
96
What is distribution
-process whereby a drug is transported from the site of absorption to the site of impact
97
how are preferred routes of admin usually chosen
based on the rate of distribution for desired effect
98
4 factors that affect distribution
- cardiovascular function
- regional blood flow
- drug storage reservoir
- physiological barriers
99
Where is drug initially distributed
- to highly perfused body areas such as the brain, heart, kidneys, liver
- if CO decreases (shock, CHF) the drug distribution becomes slower ad less predictable
100
how can body store drugs
- by binding them to proteins present with in the tissue
- either a plasma carrier protein (plasma reservoir) or a storage tissue protein (tissue reservoir)
- will delay onset of action and prolong effects
101
How does time release work
drugs bind to plasma protein (albumin) and remain inactive
| -as plasma concentration of free drug decreases, the bound drug will dissociate for use (concentration gradient)
102
4 Factors that affect distribution
- rate of perfusion
- plasma protein (albumin) binding
- accumulation in tissues
- ability to cross membranes (blood-brain barrier, placental barrier)
103
What is the blood-brain barrier
- a single layer of capillary endothelial cells that line the blood vessels entering the CNS
- cells have fatty sheath with no aqueous pores so drugs must be lipid soluble to pass through membrane
104
What drugs are easily transported by placental barrier
- steroids
- Narcotics
- Anesthetics
- Some antibiotics
it is not as selective as the blood-brain barrier
105
what is biotransformation
-process where the drug is chemically converted (metabolized) to a metabolite (another chemical)
106
What is purpose of biotransformation
- to detoxify a drug and render it less active
- liver biotransforms many drugs partially or completely
- all drugs absorbed by GI will go through liver first
107
What is the hepatic first pass event
- drugs given orally go through portal system first and liver before distributed to body
- can significantly metabolize drugs in first pass
- some drugs fully metabolize on first pass so cannot giv PO
108
why are IV doses much lower than PO
to adjust for loss of drug when it is metabolized on first pass
109
What are 2 effect from biotransformation
- transformation to less active metabolite
| - enhancement of solubility
110
What happens to biotransformation when there is liver disease
- slows metabolism
- prolongs effects
- liver is the primary site of drug metabolism
111
What is Therapeutic threshold
- minimum effective concentration of a drug necessary to cause a desired response
- below this level drug will not produce a clinical response
- at some point above this drug can be toxic or fatal
112
What is excretion
elimination of toxic or inactive metabolites from the tissues either in original form or as metabolites
113
how can drugs be eliminated artificially
by direct interventions, such as peritoneal dialysis or hemodialysis
114
what is primary site of elimination
Kidneys
- mechanism dependent on:
* passive glomerular filtration
* active tubular transport
- partial reabsorption
- hemodialysis
115
What is the effects of renal disease on elimination
- slows excretion
| - prolongs effects
116
What are 6 ways drug can be excreted
- kidneys into urine
- liver into bile
- intestines into feces
- lungs into expired air
- sweat glands (rare)
- mammary glands into milk
117
3 factors affecting elimination
- drug half-life
- accumulation
- clearance
118
What to note about shorter or increased biological half-life t1/2
- shorter t1/2 may need more frequent doses
| - hepatic disease may increase t1/2
119
with a regularly administered drug reaches a constant total body amount or steady state after how many half lives
about 5
| -once steady state reached drug concentration in blood fluctuates above and below avrg concentration
120
if time required to reach therapeutic blood concentration is too long how can you reach steady state
-initial loading dose then subsequent accumulation doses
121
What is clearance
- removal of drug from body
- slow clearance = slow rate of removal
- high clearance = rapid rate
122
What is risk with drug with low clearance rate
-may accumulate to a toxic concentration in the body unless it is administered less frequently or at lower doses
123
Consideration with drugs with high clearance rate
may require more frequent administration and higher doses than a comparable drug with a low clearance rate
124
What is Enteral drug route
-deliver meds by absorption through the GI tract
125
What are Parenteral drug route
-delivers meds via router other than the GI tract
126
What are the 5 Enteral routes
- oral
- orogastric (OG) / Nasogastric (NG)
- Sublingual (SL) (excellent absorption very vascular)
- Buccal (cheek/gum absorbed through mucous membrane)
- Rectal (PR) (only 1/2 drug taken goes through liver first so this route more predictable)
127
What are 8 Parenteral routes
- IV
- IO
- ET (endotracheal)
- Umbilical (newborns)
- IM
- SQ
- Inhalation
- Topical (percutaneous)
128
What are 10 drug forms
- liquid
- solid
- gas
- suppositories
- inhalants
- sprays
- creams
- lotions
- patches
- lozenges
129
Why are drug forms chosen in some cases
- because of drug interactions and reactions
| - some forms are used to affect absorption rates into the body
130
5 subcategories of solid form drugs
- pills (spherically shaped)
- powders
- tablets (powder compressed into disk)
- suppositories (drug w/ wax that melts)
- capsules (gelatin container filled w/ powder)
131
What are 7 subcategories of liquid form drugs
- solutions (water or oil based)
- tinctures (alcohol extraction process)
- suspensions (doesnt dissolve in solvent)
- emulsion (suspension w/ oily substance in solvent)
- Spirits (volatile drug in alcohol)
- elixirs (alcohol and water solvent with flavoring)
- Syrups (sugar, water, drug solutions)
132
What are the actions of drugs
- Pharmacodynamics
- bind to a receptor site
- change physical properties
- chemically combine with other substances
- alter a normal metabolic pathway
133
How are drug receptors classified
by the effects they produce and may be further classified by specific effects
134
how do most drugs produce their effects
by either a drug-receptor interaction (agonist, antagonist, affinity, efficacy, types of receptors),
drug enzyme interaction, or
non-specific drug interactions
135
What is drugs effect on hormones, enzymes or metabolic functions
they can increase, decrease or replace them
| -some drugs destroy or inhibit foreign organisms or malignant cells
136
What is drug-receptor interaction
-drug action begins after the drug binds to a receptor site on the cell membrane (key lock theory)
137
What is drug enzyme interaction
- normally enzymes bind to enzyme substrate molecules to produce an effect
- drug will mimic the substrate molecules and the enzymes combine with the drug instead
- blocks normal action or results in the production of another substance
138
How do drugs altering enzymes activity work
- alter processes catalyzed by the enzymes
| - enzymes = biological catalysts (speed chemical reactions and are not changed themselves)
139
How can some drugs change cell membrane permeabillity
by blocking or opening sodium or potassium channels
140
What is non-specific drug interactions
-drugs penetrate into cells or accumulate in cell membranes to interfere with cellular function (ex. general anesthetics)
141
How do some drugs combine with other chemicals to affect body
- neutralize stomach acids (antacids)
- destroy/ inhibit bacteria or pathogens (antiseptic effect from alcohol)
- chelation of heavy metal (grabbing/ binding)
142
What are anti-metabolites
- enter biochemical reactions in place of normal substrate "competitors
- result in biologically inactive product
143
Define potency in relation to drug dose
- absolute amount of drug required to produce an effect
| - more potent drug is the one that requires lower dose to cause same effect
144
Define Threshold (minimal) dose
-least amount needed to produce desired effects
145
Define maximum effect in relation to drug dose
-greatest response produces regardless of dose used
146
How is response to drug therapy usually assessed
by observing the pharmacological effect of the drug on physiological parameters
147
When do drug interactions occur
- whenever 2 or more drugs are available in the same pt
| - the interaction can increase, decrease or have no effect on their combined action
148
6 variables influencing drug interactions include:
- intestinal absorption
- competition for plasma protein binding
- drug metabolism or biotransformation
- action at the receptor site
- renal excretion
- alteration of electrolyte balance
149
Name 6 adverse drug reactions that can cause temporary loss of function, permanent damage or death
1. secondary actions/ effects
2. Allergic/ hypersensitivity reactions
3. Idiosyncratic reaction
4. Mutagenicity
5. Carcinogenicity
6. Drug addiction
150
define secondary actions/ effects
- Side effect
- signs and symptoms of a drug reaction
- not the intended effect
151
Define allergic/ hypersensitivity reactions
-local or systemic effects due to hypersensitivity to the drug
152
define idiosyncratic reaction
- the drug reaction that is not expected (not normal for the population)
- unique to an individual
153
define Mutagenicity
- drug resistant mutants appear with common use of drug (ex. antibiotics)
- tolerance (decreased response to the same amount)
154
Define Carcinogenicity
-a drug which may cause cancer
155
Define drug addiction
behavioral pattern of:
- drug craving
- out of control usage
- overwhelming concern with obtaining drug supply
156
Define Cross Tolerance
-tolerance for a drug that develops after administration of a different drug
157
Define Tachyphylaxis
-rapidly occurring tolerance to a drug
158
Define cumulative effect
-increased effectiveness when a drug is given in several doses
159
Define drug dependance
-pt becomes accustomed to the drug's presence in his body
160
define drug interaction
-effect of one drug alter the response to another drug
161
define drug antagonism
the effect of one drug block the response to another drug
162
Define summation
-AKA additive effect, 2 drugs with the same effect are given together (like 1+1=2)
163
define synergism
-2 drugs with the same effect are given together and produce a response greater than the sum of their individual responses (ex. 1+1=3)
164
Define potentiation
one drug enhances the effect of another
165
Define Interference
-the direct biochemical interaction btw 2 drugs; one drug affects the pharmacology of another drug
166
What are 8 other factors affecting pharmacokinetics
- onset of action
- peak concentration
- duration of action
- age
- weight
- gender
- time of administration
- route of administration
167
Define onset of action
the time when the drug is sufficiently absorbed to reach an effective blood level and sufficiently distributed to its site of action to elicit a therapeutic response
168
Define peak concentration
-as the body absorbs more of the drug, the drug concentration in the blood rises, more drug reaches the site of action, and the therapeutic response increases
169
Define duration of action
-length of time that the drug concentration is sufficient in the blood to produce a therapeutic response
170
What is age affect on pharmacokinetics
- young (immature liver and kidneys)
- elderly (decreased liver and kidney function
BOTH usually require smaller doses
171
What is weight effect on pharmacokinetics
- avrg adult dosages are based on a 150lb person
- dosage should be adjusted for significantly higher or lower weights
- water comprises approx. 60% of total body weight
172
What is gender effect on pharmacokinetics
- women usually smaller and have diff ration of body fat and water
- may require smaller doses
173
what is time of administration effect on pharmacokinetics
- drugs are absorbed more rapidly if GI tract is empty
| - some drugs irritate the GI tract and should be taken w/ food
174
what is route of administration effect on pharmacokinetics
- IV route faster and needs lower dose
| - PO slower and needs bigger dose
175
What are 4 sources of drug info you can refer to
- CPS (compendium of pharmaceuticals and specialties
- Health canada drug product database
- physician's desk reference
- drug information
