Exam 2 Pharm Study guide
Chapter 15
Adrenergic agonists
Sympathetic responses
Stimulation of sympathetic nervous system or use of adrenergic drugs can cause
dilation of pupils and bronchioles; increased heart rate; constriction of blood vessels; relaxation
of muscles in GI tract, bladder, and uterus.
Effects of adrenergic agonists at receptors
Alpha 1 receptor
Increases cardiac contractility, vasoconstriction
Dilates pupils, decreases salivary gland secretion
Increases bladder and prostate contraction
Alpha 2 receptor
Inhibits norepinephrine release
Promotes vasodilation and decreased bp
Decreases GI motility and tone
Beta 1 receptors
Increases cardiac contractility, heart rate
Increases renin secretion and increases bp
Beta 2 receptors
Decreases GI tone and motility
Bronchodilation
Increases blood flow t=in skeletal muscles
Relaxes smooth muscle of uterus
Activates liver glycogenolysis
Increases blood glucose
Dopaminergic
Located in the renal, mesenteric, coronary, and cerebral arteries
Vasodilation-increases flow
Neurotransmitter inactivation
Inactivation by
Reuptake of transmitter back into neuron
Enzymatic transformation or degradation
MAO inside neuron
COMT outside neuron
Diffusion away form the receptor
Drugs halt termination of neurotransmitter by inhibiting
Norepinephrine reuptake
Norepinephrine degradation
After the transmitter has performed its function, the action must be stopped to prevent
prolonging the effect
, Two enzymes that inactivate the metabolism of norepinephrine are monoamine oxidase
(MAO) and Catechol-O-methyltransferase (COMT).
Classification of adrenergic agonists
Direct-acting (epinephrine; norepinephrine)
Directly stimulates adrenergic receptor
Indirectly acting (amphetamine)
Stimulates release of norepinephrine from terminal nerve endings
Mixed acting (ephedrine)
Stimulates adrenergic receptor sties and stimulates release of norepinephrine
form terminal nerve endings
Also called sympathomimetics
Catecholamines
Catecholamines
Produce sympathetic response
Endogenous
Epinephrine, norepinephrine, dopamine
Synthetic
Isoproterenol, dobutamine
Noncatecholamines
Stimulate adrenergic receptors
Most have longer duration of action than endogenous and synthetic
Phenylephrine, metaproterenol, albuterol
Catecholamines: chemical structures of a substance that can produce a
sympathomimetic response
Noncatecholamines: stimulate adrenergic receptors
Many adrenergic agonists stimulate more than one adrenergic receptor site
ex. Epinephrine acts on alpha 1, beta 1, and beta 2
Epinephrine
Nonselective
Action
Alpha 1 increases the blood pressure
Beta 1 increases heart rate
Beta 2 promotes bronchodilation
Contraindications
Cardiac dysrhythmias, hypertension
Hyperthyroidism, DM
Pregnancy
Epinephrine is a nonselective, as it excites three different adrenergic receptors
approximately equally.
Action
Inotropic: strengthens myocardial contraction, increasing cardiac output
Vasoconstrictor: increases heart rate and systolic BP
Bronchodilator
Uses
, Anaphylaxis, anaphylactic shock
Bronchospasms, status asthmaticus
Cardiogenic shock, cardiac arrest
Side effects/adverse reactions
Cardiac dysrhythmias, palpitations, tachycardia, hypertension, dizziness,
headache, sweating, insomnia, restlessness, tremors, hyperglycemia
Drug interactions
Beta blockers
Decreases epinephrine action
Digoxin
Causes cardiac dysrhythmias
TCAs and MAOIs intensify and prolong effects
Nursing interventions
Monitor BP, heart rate, urine output
Report tachycardia, palpitations, tremors, dizziness, hypertension
Monitor IV site for infiltration
Antidote: phentolamine mesylate (regitine)
Avoid cold medications, and diet pills if hypertensive, diabetic, CAD, or
dysrhythmic
Avoid adrenergic when breastfeeding
Avoid continuous use of adrenergic nasal sprays
Pt should be placed on cardiac monitor for early detection of dysrhythmias.
Monitor urine output for early detection of decreased renal perfusion
Albuterol
Selective
Acts on beta 2 adrenergic receptors
Promotes bronchodilation
Uses
Treats bronchospasm, asthma, bronchitis, COPD
Caution
Severe cardiac disease
Hypertension, hyperthyroidism
DM, pregnancy
Renal dysfunction
Side effects/adverse reactions
Tremors, nervousness, restlessness, dizziness, tachycardia, palpitations, cardiac
dysrhythmias
Drug interactions
May increase effect with other sympathomimetics, MAO inhibitors, and TCAs
Antagonize effect with beta blockers
Nursing process: adrenergic agonist
Assessment
Determine the patients health history
Assess the patients drug history
, nursing interventions
monitor iv site frequently when administering norepinephrine or dopamine
because extravasation of these drugs causes tissue damage and necrosis within 12hrs
monitor ECG for dysrhythmias when adrenergic agonists are given IV
explain that continuous use of nasal sprays or drops that contain an adrenergic
agonist may result in rebound nasal congestion
evaluation
Adrenergic antagonists
Block effects of adrenergic neurotransmitter
Block alpha and beta receptor sites
Directly by occupying receptors
Indirectly by inhibiting release of neurotransmitters epinephrine and
norepinephrine
Types
Alpha-adrenergic antagonists
Selective
Nonselective
Beta-adrenergic antagonists
Selective
Nonselective
Also called adrenergic blockers and sympatholytics
Effects of adrenergic antagonists at receptors
Alpha 1
Vasodilation, dizziness
Orthostatic hypotension, reflex tachycardia
Pupil constriction
Suppresses ejaculation
Reduces contraction of smooth muscles in bladder neck and prostate
Beta 1
Reduces cardiac contractility
Decreases pulse
Beta 2
Bronchoconstriction
Contracts uterus
Inhibits glycogenolysis
Leads to hypoglycemia
Alpha adrenergic antagonists
Drugs that inhibit a response at alpha-adrenergic receptors site
Selective
Block alpha 1
Nonselective
Block alpha 1 and 2
Action
Promotes vasodilation
Chapter 15
Adrenergic agonists
Sympathetic responses
Stimulation of sympathetic nervous system or use of adrenergic drugs can cause
dilation of pupils and bronchioles; increased heart rate; constriction of blood vessels; relaxation
of muscles in GI tract, bladder, and uterus.
Effects of adrenergic agonists at receptors
Alpha 1 receptor
Increases cardiac contractility, vasoconstriction
Dilates pupils, decreases salivary gland secretion
Increases bladder and prostate contraction
Alpha 2 receptor
Inhibits norepinephrine release
Promotes vasodilation and decreased bp
Decreases GI motility and tone
Beta 1 receptors
Increases cardiac contractility, heart rate
Increases renin secretion and increases bp
Beta 2 receptors
Decreases GI tone and motility
Bronchodilation
Increases blood flow t=in skeletal muscles
Relaxes smooth muscle of uterus
Activates liver glycogenolysis
Increases blood glucose
Dopaminergic
Located in the renal, mesenteric, coronary, and cerebral arteries
Vasodilation-increases flow
Neurotransmitter inactivation
Inactivation by
Reuptake of transmitter back into neuron
Enzymatic transformation or degradation
MAO inside neuron
COMT outside neuron
Diffusion away form the receptor
Drugs halt termination of neurotransmitter by inhibiting
Norepinephrine reuptake
Norepinephrine degradation
After the transmitter has performed its function, the action must be stopped to prevent
prolonging the effect
, Two enzymes that inactivate the metabolism of norepinephrine are monoamine oxidase
(MAO) and Catechol-O-methyltransferase (COMT).
Classification of adrenergic agonists
Direct-acting (epinephrine; norepinephrine)
Directly stimulates adrenergic receptor
Indirectly acting (amphetamine)
Stimulates release of norepinephrine from terminal nerve endings
Mixed acting (ephedrine)
Stimulates adrenergic receptor sties and stimulates release of norepinephrine
form terminal nerve endings
Also called sympathomimetics
Catecholamines
Catecholamines
Produce sympathetic response
Endogenous
Epinephrine, norepinephrine, dopamine
Synthetic
Isoproterenol, dobutamine
Noncatecholamines
Stimulate adrenergic receptors
Most have longer duration of action than endogenous and synthetic
Phenylephrine, metaproterenol, albuterol
Catecholamines: chemical structures of a substance that can produce a
sympathomimetic response
Noncatecholamines: stimulate adrenergic receptors
Many adrenergic agonists stimulate more than one adrenergic receptor site
ex. Epinephrine acts on alpha 1, beta 1, and beta 2
Epinephrine
Nonselective
Action
Alpha 1 increases the blood pressure
Beta 1 increases heart rate
Beta 2 promotes bronchodilation
Contraindications
Cardiac dysrhythmias, hypertension
Hyperthyroidism, DM
Pregnancy
Epinephrine is a nonselective, as it excites three different adrenergic receptors
approximately equally.
Action
Inotropic: strengthens myocardial contraction, increasing cardiac output
Vasoconstrictor: increases heart rate and systolic BP
Bronchodilator
Uses
, Anaphylaxis, anaphylactic shock
Bronchospasms, status asthmaticus
Cardiogenic shock, cardiac arrest
Side effects/adverse reactions
Cardiac dysrhythmias, palpitations, tachycardia, hypertension, dizziness,
headache, sweating, insomnia, restlessness, tremors, hyperglycemia
Drug interactions
Beta blockers
Decreases epinephrine action
Digoxin
Causes cardiac dysrhythmias
TCAs and MAOIs intensify and prolong effects
Nursing interventions
Monitor BP, heart rate, urine output
Report tachycardia, palpitations, tremors, dizziness, hypertension
Monitor IV site for infiltration
Antidote: phentolamine mesylate (regitine)
Avoid cold medications, and diet pills if hypertensive, diabetic, CAD, or
dysrhythmic
Avoid adrenergic when breastfeeding
Avoid continuous use of adrenergic nasal sprays
Pt should be placed on cardiac monitor for early detection of dysrhythmias.
Monitor urine output for early detection of decreased renal perfusion
Albuterol
Selective
Acts on beta 2 adrenergic receptors
Promotes bronchodilation
Uses
Treats bronchospasm, asthma, bronchitis, COPD
Caution
Severe cardiac disease
Hypertension, hyperthyroidism
DM, pregnancy
Renal dysfunction
Side effects/adverse reactions
Tremors, nervousness, restlessness, dizziness, tachycardia, palpitations, cardiac
dysrhythmias
Drug interactions
May increase effect with other sympathomimetics, MAO inhibitors, and TCAs
Antagonize effect with beta blockers
Nursing process: adrenergic agonist
Assessment
Determine the patients health history
Assess the patients drug history
, nursing interventions
monitor iv site frequently when administering norepinephrine or dopamine
because extravasation of these drugs causes tissue damage and necrosis within 12hrs
monitor ECG for dysrhythmias when adrenergic agonists are given IV
explain that continuous use of nasal sprays or drops that contain an adrenergic
agonist may result in rebound nasal congestion
evaluation
Adrenergic antagonists
Block effects of adrenergic neurotransmitter
Block alpha and beta receptor sites
Directly by occupying receptors
Indirectly by inhibiting release of neurotransmitters epinephrine and
norepinephrine
Types
Alpha-adrenergic antagonists
Selective
Nonselective
Beta-adrenergic antagonists
Selective
Nonselective
Also called adrenergic blockers and sympatholytics
Effects of adrenergic antagonists at receptors
Alpha 1
Vasodilation, dizziness
Orthostatic hypotension, reflex tachycardia
Pupil constriction
Suppresses ejaculation
Reduces contraction of smooth muscles in bladder neck and prostate
Beta 1
Reduces cardiac contractility
Decreases pulse
Beta 2
Bronchoconstriction
Contracts uterus
Inhibits glycogenolysis
Leads to hypoglycemia
Alpha adrenergic antagonists
Drugs that inhibit a response at alpha-adrenergic receptors site
Selective
Block alpha 1
Nonselective
Block alpha 1 and 2
Action
Promotes vasodilation
