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Flashcards in Principles of Pharmacology Deck (128):
1

Pharmocology

Study of how various substances interact with or alter the function of living organisms

2

Opium Expolsuion Act

In 1909 was created to stop import of opium

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Food, Drug, and Cosmetic Act

In 1938 the US FDA was given enforcement authority for rules requiring that new drugs were safe and pure

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FDA

Responsible for approving new drugs

5

Controlled Substances Act

Classifies certain medications into five categories with potential of abuse and addiction

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Schedule 1

High Abuse potential:
May not be prescribed, dispensed, used or administered for medical use and has no recognized medical purpose
Ex: heroin, marijuana, lsd

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Schedule 2

High Abuse Potential:
Has a medical purpose but is required t be under constant lock and key, records kept and proper storage
Ex: fentanyl, Ritalin, cocaine

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Schedule 3

Lower Potential Abuse:
Must remain under lock and key with records kept and proper storage
Ex: hydrocodone, codeine, ketamine

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Schedule 4

Lower Potential Abuse:
S/a 2-5
Ex: diazepam, lorazepam, midazolam

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Schedule 5

Lower Potential Abuse:
S/a 2-5
Ex: narcotic cough drops

11

Synthetic

Made in a labratory

12

Sources of Medication exampls

Plant: atropine, aspirin, digoxin, morphine
Animal: heparin, antivenom, insulin
Microorganism: streptiknoase, antibiotics
Minerals: iron, magnesium, Sulfate, lithium

13

Medication Name

Given three different names
Chemical: very long name (sodium bicarbonate)
Generic Name: usually contain stem at the end of the name to link it to other medications lam, pine, lol, lal
Brand Name: Lasix, Tamiflu, Lopressor makes it easier to remember drug generic name

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Pharmacodynamics

When a medication alters a function or process in the body

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Pharmokinetics

The action of the body on a medication

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Receptor Site with Medication

Either
1: ion passages may open or close
2: bio mechanical messenger becomes activated initiating other reactions in cell
3: normal cell function prevented
4: normal or abnormal function of cell begins

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Exogenous

From outside of the body

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Agonist Medications

Initiate or alter a cellular activity by attaching to receptor sites, prompting a cell response
Ex: opiates

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Antagonist Medications

Prevent endogenous or exogenous agonist chemicals from reaching cell receptor sites and initiating or altering a particular cellularactivity
Ex: nalaxone

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Affinity

Ability of a medication to bind with a particular receptor site

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Medication Concentration and Affinity

Determine how many receptor sites are bound by that medication
-only certain amount of receptors and all receptors can be taken up

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Minimum Concentration

Certain minimum of medication must be present to activate cellular activity

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Threshold Level

When initiation or alteration of cellular activity begins

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Potency

The concentration of a medication required to intpitiate a cellular response
-when potency is low, a higher concentration is needed

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Efficacy

Ability to initiate or alter cellular activity in a therapeutic or desired manner

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One-Response Curve

Relationship of medication dose or concentration and efficacy
-once threshold is reached increasing dose increases efficacy until maximum effect range is reached then increasing dose has no effect

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Competitive Antagonists

Temporarily bind with cellular receptor sites, displacing agonist chemicals
-until wasted naturally by kidneys

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Noncompetetive Antagonists

Premnently bind with receptor sites and prevent activation by agonist chemicals
-effects continue until new receptor sites are made or until new cells are made
-Ex:
Ketamine NCA of Glutamate of the CNS
Aspirin NCA of Cyclooxygenase causing antiplatelet effects

29

Partial Agonist

Attach to cellular receptor sites but do not cause as much change as other agonists
-effectively lower efficacy of other agonists

30

Chelating Agents

Bind with heavy metals such as lead, mercury, and arsenic in the body nod creating a compound that can be eliminated

31

Diuretic

Draws excess water from certain body tissues including the brain and the eyes while enhancing excretion of urine by the kidneys

32

Medication Distribution

Distribute into either water, lipids or fat, and protein

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Water-Soluble medication

Higher weight based dosing must be administered to infants because they have a higher percentage of water compared to adults and elederly
Ex: digoxin

34

Fat and Lipid medication

Require higher weight based doses in elederly people because of a higher body fat percentage and increased fat distribution
Ex: benzodiazepines

35

Paradoxical Reaction

Clinical effects opposite from desired effect

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Formula Ideal Body Weight

In KG
Men: 50 + (2.3 times patients height in inches over 5 feet)
Women: 45.5 + (2.3 times patients height in inches over 5 feet)

37

Temperature

Hyper and hypothermia can effect body absorption of medication
-fever causes tachycardia that increases hepatic blood flow increasing initial metabolism of drugs in the liver and decreasing amount of drug delivered to circulation
-hypothermia impairs acls Medications. Atropine and lidocaine generally seen as ineffective.

38

Genetic Factors

Primary Pulmonary Hypertension: may have acute decompensation when vasopressor medications are used
Aspirin: may precipitate hemolysis in patients with bleeding disorders
Sickle Cell: medications such as lasix (diuretics) or alpha 1 agonists may fatally worsen condition

39

Pregnancy

Hematocrit (percentage of RBC's in plasma decrease due to increase in plasma)
Categories Desgined:
A- no risk to fetus
B- may have been effect in rates but none shown in women
C- are adverse effects on pregnancy. Drugs given only if benefit outweighs risk
D- fetal risk apparent.
X- fetal abnormalities. Contraindicated in pregnant women.

40

Placebo Effect

Fake medication given and still seen to cause change

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Therapeutic (desired) Response

One that achieves a desired result by medication administration

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Cumulative Action

Using multiple medications to achieve desired result

43

Adverse Medical Effects
(untoward effects)

Clinical changes, caused by medication, that are not desired and cause some degree of harm or discomfort to the patient
Ex: hypoglycemia after insulin administration, bradycardia after beta blocker, and allergic reaction

44

Stevens Johnsons Syndrome

Severe possible fatal medication administration reaction that mimics a burn

45

Idiosyncratic Reaction

Abnormal susceptibility to a medication due to genetic factors, dysfunction of metabolic enzyme, and peculiar to patient

46

Median Lethal Dose

LD50: weight based dose that caused death in 50% of animals tested

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Median Toxic Dose

TD50: 50% of animals tested had toxic effect at or above weight based dose

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Median Effect Dose

ED50: does not harm and achieves desired effect

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Therapeutic Index

Relationship between ED and LD or TD
-If a large gap between lethal and effective it is relatively safe. If not, must be used very carefully

50

Medication Sensitivity

Adverse reaction not desired such as hives or allergic reaction

51

Tolerance

When a medication is constantly taken and causes the patient to have a decrease in efficacy

52

Down Regulation

When a patient builds a tolerance it decrease available cell receptors

53

Cross Tolerance

When using a certain medication in a class becomes tolerant to medications of the same class such as benzodiazepines

54

Tachyphylaxis

Repeated doses of medication within a short time frame rapidly causing tolerance making medication virtually ineffective
Ex: dobutamine, nitroglycerin

55

Stimulant

Increase in physical, mental and emotional performance
Ex: caffeine, cocaine, amphetamines
Increase HR and BP

56

Depressant

Decrease CNS causing section, reap depression, bradycardia, hypotension.
Ex: benzo's, alcohol, opiods

57

Interference

When patients take other drugs that interfere with desired effect of given drug by paramedic

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Onset

When medications begin to work

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Peak

Medication is at max effectiveness

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Duration of Action

How long medication causes effect on body

61

Bioavailability

Chosen route of administration determines percentage of unchanged medication that reaches circulation

62

Synergism

1+1=6
When two medications of similar effect combine to form a greater effect than sum of medications
Ex: benzodiazepines with opiod analgesics

63

Potentiation

Effect greatly enhanced by presence of another medication
Ex: phenegran given to increase effects of codeine or other antitussives

64

First Pass Metabolism

Drug travels from GI to portal vein to liver to be metabolized
-when liver is damaged, less first pass metabolism happens and the drug reaches systemic circulation with a greater bioavailability

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IN

Intranasal
Close to 100% bioavailability
Good as an IV without attempting a line and has same effects almost
Ex: sublimaze, versed, nalaxone

66

IV

100% bioavailability
Sympathomimetic and electrolyte solutions scan cause severe tissue damage if infiltrated

67

IO

Any IV medication can be given IO
CAN BE LEFT IN PLACE FOR UP TO 24 hours
Contraindicated in bone fractures, bone diseases or skin infection over area

68

IM

Intramuscular
75-100% bioavailability
Absorption determined by perfusion to muscle and accuracy of administration

69

SC

Subcutaneous
Abdomen or skin overlaying tricep good landmarks

70

Rectal

Preferred over oral
Used in seizures, unconscious, vomiting or unable to swallow
Not usually subject to first pass metabolism
90-100% bioavailability
Suppository form, lubricated and entered into rectum ditspally preferred over proximal rectum
Rectal Dose often higher than oral or IV dose

71

Active Metabolites

Altering cell process or body function

72

Cytochrome P-450 System

Where most biotransformation occurs. System in the liver that uses a complex, enzyme based process to alter the chemical structure of a medication or other chemical.
Certain pathways within the Cp-450 system are responsible for the metabolism of different medication groups

73

Kidneys, skin, lungs, GI tract

Other biotransformation occurs
-other words, biotransformation makes medications and chemicals more water soluble and easier for the kidneys and other organs to eliminate from the body

74

Medication Elimination

Primarily eliminated from the kidneys
And excreted into urine

75

Zero Order Metabolism

Fixed amount of substance is removed during a certain period, regardless of total amount in the body
Ex: alcohol, duration of intoxication is related to initial plasma levels

76

First-order Metabolism

Rate of elimination directly influenced by plasma levels of the substance
-quantified by medication half life

77

6 Rights

Patient
Time
Dose
Medication
Route
Documentation

78

Benzodiazepines

Diazepam, Lorazepam, Midazolam
-antiseizure, anxiolytics, sedative properties
-high doses needed for airway sedation
-hypotension
-only administered to pregnant patients during life threatening situations; Class D
-Romazicon competitive benzodiazepines antagonist

79

Chemical Paralytic Agents

Provide muscle relaxation that facilitates airway placement
-Allow better visualization of cords compared to just sedatives
*Normal* nerve cells release acetylcholine which binds to nicotonic receptor sites on muscle cells causing contraction. Paralytic bind and antagonize nicotonic receptor sites preventing activation by Ach.

80

Succinycholine

Competitive depolarizing paralytic agent
-reaches nicotonic receptors and causes a brief activation known as fasiculations and prevents further Act of acetylcholine
-Rapid Onset 30-60 seconds and brief Duration 3-8 minutes
-Contraindicated: hyperkalmeia, Bradycardia, elevate intraocular pressure, malignant hyperthermia, burns, lumbi Indian

81

Fasiculations

Muscles twitch and move temporarily due to activation of nicotonic receptors

82

Malignant Hyperthermia

Causes a fast rise in body temperature and causes severe muscle contractions when given anasthetic and is passed down from families

83

Nondepolarizing paralytics

Compete with Ach at nicotonic receptor sites. They occupy but not activated receptor sites, preventing Ach activation
-Longer duration than depolarizing paralytic and less adverse reactions

84

Sedative Hypnotic Agents used in Airway

Etomidate and Ketamine are two ultra short acting sedative medications used to facilitate airway management
-Etomidate: imidazole derivative with minimal effect on BP. Onset is 30-60 seconds Duration is 5 minutes
No more than one dose given
-Ketamine: causes profound disassociation and general anesthesia. Maintains BP and HR but raises ICP so not good for head injury patients. Causes some degree of bronchodilator.

85

Beta Agonist Medications

Beta Adrenergic Medications remain primary treatment for acute bronchospasm with asthma, COPD, and others.
-walls of lower airways contain smooth muscle that contract or relax in response to biochemical changes and external irritants
-beta-2 receptor sites on bronchial smooth muscle cause muscle relaxation and bronchodilator effects
-nor Epi and Epi natural occurring beta 2 agonists
-beta agonists medications can be selective, or non selective, only targeting beta 1 or beta 2.
-Some beta 2 medications cause beta 1 effects such as Albuterol that causes tachycardia
-Albuterol can facilitate uptake of potassium

86

Mucokinetic and Bronchodilator

Atrovent
-Antagonizes muscarinic receptors causing bronchodilation and decrease mucus in upper and lower airways. Cardiovascular effects limited due to poor systemic absorption.

87

Corticosteroids

Administered to reduce airway inflammation to improve oxygenation and ventilation
-Methylprednisolone and Decadron
-Have immunosupressant properties and can alter Endocrine functions

88

Cardiovascular Medications

Antidysrhytmic Meds specifically target cells within the heart to resolve a dysrhytmia or suppress ectopic focci (sites conducting other than primary pacemaker)

89

Vaughan Williams classification Scheme

The classification of dysrhythmia Medications based upon mechanism of action rather than specific groups

90

Cardiac Cycle

0-4 phases
Cycle begins at 4

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Phase 4

Cardiac cells are at rest waiting for generation of spontaneous impulse from within (automaticity)
-coincides with diastole of the heart

92

Phase 0

Begins with rapid influx of sodium ions through channels in the cardiac cell and
Potassium ions slowly begin to exit the cell and depolarization occurs

93

Phase 1

Sodium influx decreases while potassium continues to leave the cell

94

Phase 2

Movement of calcium into the cardiac cell
While potassium continues to leave

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Phase 3

Calcium movement ceases with continued outflow of potassium
-Phases 2-3 repolarization and myocardial contraction occur

96

Absolute Refractory Period

During phases 0-3 no additional depolarization may occur because of external stimuli
-ensures that a certain amount of time passes between myocardial contractions

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Relative Refractory Period

Immediately follows absolute Refractory Period which is a brief window to initiate depolarization

98

Phases

_____|'''---,,,,,____
___= phase 4
| = phase 0
''' = phase 1
--- = phase 2
,,,, = phase 3

99

Class I Antidysrhytmics

Slow movement of sodium through channels in certain cardiac cells
-Procainamide and Lidocaine
-Lidocaine blocks sodium channels through purkinje fibers and ventricle, effectively resolving various ventricular dysrhtymias and suppressing ectopic foci

100

Class II Antidysrhytmics

Beta Blockers
-Directly inhibit catecholaimnes (Epi nor Epi)
-metoprolol and lebatolol
-Metoprolol beta blocker used to reduce heart rate during MI and in certain atrial tachycardias. Reduces heart rate with reduction in BP

101

Class III Antidysrhytmics

Increase duration of phases 1, 2, and 3
By extending cellular action potential, these medications prolong the absolute Refractory Period treating atrial or ventricular tachycardias
-Amiodarone: atrial and ventricular tachycardia by blocking sodium potassium channels

102

Class IV Antidysrhytmics

Calcium Channel Blockers
Used for reducing BP or heart rate
Anatagnize certain calcium receptor sites which slow conduction through av node, decrease automaticity of ectopic focci, and decrease dromotropic effects of cardiac conduction
-Cardiazem and Verapamil : used for control of heart rate in patients with a fib or a flutter. Cardiazem has less effect on BP
-Antidote is Calcium Gluconate or Chloride

103

Adenosine

Member of fifth and unnamed antidysrhythmic
Treats PSVT or SVT
-Decreases cardiac conduction dromotropic effects and prolongs relative absolute Refractory Period producing several second pause. Half life less than 10 seconds.

104

ACE Inhibitors

Antagonize the system that causes vasoconstriction and fluid retention in response to hypotension or hypoperfusion
-decrease blood pressure and cardiac afrerload
-treats hypertension, myopathy, CHF
-angiodema may occur when taking ACE inhibitors

105

Anticholinergics

Vagus Nerve is biggest parasympathetic Nerve in body responsible for heart lungs and digestive tract
-vagus nerve release aCH that acts on muscarinic 2 receptors in the heart to decrease heart rate and can cause activation of fluid mucus to accumulate
-Atropine: competitive muscarinic receptor antagonist that decreases effect of acetylcholine on heart effectively raising heart rate. Used when suspected vagus nerve is the problem such as patient strains, mechanical pressure applied to neck, and is ineffective in high degree heart blocks
-used before airway manipulation that may stimulate vagus nerve
-low dose < .1-.2 mg can cause paradoxical bradycardia

106

Catecholamines

Naturally occurring chemicals in the body that stimulate receptor sites in sympathetic nervous system
Epi, nor Epi, dopamine

107

Sympathomimetics

Not naturally found within the body. Mimic naturally occurring sympathetic.

108

Dopamine

Different affects at different doses due to different sites that the affinity of the medication begins to work on
-Dopaminergic Receptor Sites worked on at
2-5mcg/kg/min causing renal and mesenteric artery vasodilation
-Beta 1 Receptor sites activated at 5-10mcg/kg/min causing increased heart rate and increased contractility
-Alpha Receptor sites activated at 10-20 mcg/kg/min causing profound vasoconstriction

109

Vasodilators

Used for hypertension, CHF, mi, cardiogenic Shock
Nitroglycerin: vasodilator that primarily dilates veins and coronary arteries decrease cardiac preload, reducing oxygen demand, and improving circulation
Nitroprusside is potent IV vasodilator affecting smooth muscle of the veins and arteries. Used for malignant hypertension.

110

Diuretics

Correct volume overload such as CHF and pulmonary edema to improve respiration.
-Furosemide causes renal artery dialation and promotes urinary excretion working on distal loop of henle
-Mannitol osmotic diuretic that is used to decrease ICP. Osmotic Diuretics can target specific tissues decreasing pressure in the brain and eyes

111

Plasma

Increases clotting factors in body 225-250ml of plasma just like blood

112

RBC's

Correct anemia in hypovolemia patients
-come packaged in 225-250 ml of RBC's

113

Platelets

Administered to correct thrombocytopenia
Or a low platelet level causes by trauma, hemmorage, and anticoagulant medications
-must be blood type and Rh compatible

114

Anticoagulants

Impair the function of clotting or coagulation chemicals in bloodstream
-Enhance the function of substances in the blood that inhibit clot formation and prevent formation of new clots and the growth of existing clots but they do NOT dissolve existing blood clots
-Heparin : enhance antithromib III to inhibit blood coagulation

115

Antiplatelets

Reduces clumping of platelets preventing new thrombus or extension of new clot
-Aspirin : prevent thrombus formation
-Plavix and Ticlid also antiplatelets

116

Fibrinolytics

Dissolve blood clots in arteries and veins

117

Analgesics

Stimulate opiod receptors in body to relive pain
Medications act on Mu opiod receptors causing respiratory depression, hypotension
-Demerol, Dilaudid, Morphine, Fentanyl,
-Morphine cause nausea/vomiting in 30% of patients and may also cause histamine release causing itching

118

Phenytoin and Fosphenytoin

Dilantin and Cerebyx used to prevent seizure activity

119

Histamine 2 Receptor Antagonists

Decrease acid in stomach, protecting against ulcers or other GI issues
-Zantac, Tagamet, Pepcid (famatodine)

120

Antiemetics

The 'zine'
Phenegran is an antiemetic to help with nausea and vomiting
Activate dopaminergic receptors in brain that inhibit emesis
-Ondansetron and 'trons' are 5-HT3 Receptor Antagonists and may cause potential QT prolongation
-5-HT3 are receptors present in brain that prdouce some reasons for vomiting

121

Acetaminophen

Tylenol is an antipyretic and analgesic
Elevated levels can cause liver damage

122

Calcium Preperations

Used for:
-Antidote to ca channel blocker OD
-Mag Sulfate toxicity
-Dysrhythmia prevention with hyperkalemia
-Hypocalcemia
-Calcium restoration after HFl acid burn
-Prevent hypotension with verapamil

123

Diphenhydramine

Benadryl is a competitive histamine 1 receptor Antagonists preventing recptor activation of histamine release
-Anaphylaxis
-Allergic Reaction
-Sedative
-Anitussive
-Dystonic Reaction
-Pruritus
-Rinorrhea dries mucous membranes

124

Glucagon

Converts glycogen stores in liver into glucose for hypoglycemia
-Beta Blocker overdose by producing chronotropic and inotropic effects but require a lot
-Upper Airway Obstruction by relaxing smooth muscle in the GI tract possibly allowing object to pass into stomach for disgestion

125

Ketorolac

Toradol, non steroidal antiinflammatory that inhibits prostaglandin synthesis, treating both pain and inflammation.
-Avoid with GI bleed or similar disorder

126

Mag Sulfate

IV electrolyte that treats:
-Torsades
-Hypomagnesia, common in malnourished patients from alcoholism
-Seizures in pregnant patients with pre or eclampsia
-Bronchodilators for Refractory asthma

127

Sodium BiCarb

Alkilizing agent that is used for metabolic acidosis
-Raised blood pH
-Stabilize profound hyperkalemia
-Tricylic Antidepressnt OD
-Promote urinary secretion of certain tissue waste products
-Use din crush injuries for built up of lactic Acid
Wipes out catecholamines delivered since catecholamines are acidic.

128

Thiamine

Vitamins B1 an corrects B1 deficiency in malnourished or chronic alcoholic patients
-deficiency in thiamine can cause wernicke encephalopathy, neurological disorder exacerbated by lack of thiamine and use of dextrose