8-19 Adrenergic Agonist / Antagonist Flashcards
ALPHA 1 RECEPTOR
Tissues - Actions (3)
(1) Most vascular smooth muscle- contracts (inc. vascular resistance)
(2) Pupillary Dilatormuscle- contracts (myDriasis)
(3) Internal Urethral Sphincter- contracts
ALPHA 2 RECEPTOR Tissues- Actions (3)
(1) Adrenergic and cholinergic nerve terminals- inhibits transmitter release (2) Platelets- stimulates aggregation (3) Some vascular smooth muscle- contracts
BETA 1 RECEPTOR
Actions (2)
(1) Heart- Stimulates rate and force
(2) Juxtaglomerular cells- Stimulates renin release
BETA 2 RECEPTOR
Tissues-Actions (4)
(1) Relaxes RUV - (Respiratory, Uterine and Vascular) smooth muscle
(2) Liver- stimulates glycogenolysis
(3) Pancreatic B cells- stimulates insulin release
(4) Somatic motor nerve terminals (voluntary muscle)- causes tremor
BETA 3 RECEPTOR Tissues-Actions
(B1 and B2 may also contribute) (1) Fat cells- stimulates lipolysis
DOPAMINE 1 RECEPTOR Tissues-Actions
(1) Renal and other splanchnic blood vessels- vasoDilates (reduces resistance)
DOPAMINE 2 RECEPTOR Tissues-Actions
(1) Nerve terminals- inhibits adenylyl cyclase
Timolol: Half-Life
4 hours
Timolol: Mechanism of Action
General B-blocker
Timolol: Indication
Glaucoma
Nadolol: Half-Life
20-24 hours
Nadolol: Mechanism of Action
General B-blocker
Nadolol: Indication (2)
Long term angina, hypertension
Atenolol: Mechanism of Action
B1-blocker
Atenolol: Indication (3)
Hypertension, angina, MI
Metoprolol: Mechanism of Action
B1-antagonist
Metoprolol: Indication (2)
Hypertension, long-term angina rx
Pindolol: A: Mechanism of Action B: Because of its MOA, it has less _______ effect on the heart.
A: B-antagonist with partial agonist activity at both B1 and B2 adrenergic R B: Since some B signal remains (partial agonist), partial agonist have less BRADYCARDIC effect, thus should be used when patients are less tolerant to bradycardic effects.
Pindolol: A: Indication B: Therapeutic benefit is good when (indication) is due to _________.
A: Hypertension B: Therapeutic benefit is good when HTN is due to HIGH SYMPATHETIC OUTPUT since blockade of endogenous agonist will predominate over partial agonist effect of drug.
Esmolol: Half-life
~9 minutes
Esmolol: Mechanism of Action
B1-blocker
Esmolol: A: Indication (3) B: Esmolol has a very ____ half life, so it is given ____(dosage form) in _______ crisis, _____ angina and _______
Esmolol: A: Indication: -HTN Crisis -Angina (unstable) -Supraventricular tachycardia B: Esmolol has a very SHORT half life (9 min), so it is given IV in hypertensive crisis, unstable angina, SVT
Phenoxy-benzamine: Mechanism of Action
General alpha-blocker
Phenoxy-benzamine: Indication
Pheochromo-cytoma
Phentolamine: Mechanism of Action
General alpha-blocker
Phentolamine: Indication
rx for pheochromocytoma before surgery
Prazosin: Mechanism of Action
[Alpha 1 BLOCKER]
What are the three cardioselective B1-blockers?
Metoprolol, Atenolol, Esmolol
What are the cardiovascular effects of the cardioselective B1-blockersβ¦. -HR/Contractility? -Renin Release? -Vasoregulation?
Reduced heart rate and contractility, reduced renin release, reduced vasoconstriction (due to the reduced angio II) [same as non-selective B blockers]
Cardioselective B1 BLOCKERS: Therapeutic use (3)
Hypertension, angina, arrhythmia
Cardioselective B1-blockers: Toxicity (4)
Depression, insomnia, hypotension, bradycardia
Cardioselective B1-blockers: Contraindications (2)
- Pt with 2nd/3rd degree heart block -Pt with cardiogenic shock
EPINEPHRINE Half-Life
Short
EPINEPHRINE MOA
EPINEPHRINE MOA: [General alpha Agonist{HIGH CONCENTRATION} and [General Beta agonist{low concentration}] βwith low effort youβll get a Bβ¦.with HIGH EFFORT YOUβLL GET AN Aβ
EPINEPHRINE ELIMINATION
COMT β> Urine
EPINEPHRINE INDICATION (4)
EPINEPHRINE Indication: β’Anaphylaxis β’Shock β’Cardiac Arrest β’Heart Block
EPINEPHRINE TOXICITY
Arrhythmias
NorEpi HALF-LIFE
short (just like EPi)
NorEpi
MOA (2)
[General alpha agonist] + [Beta 1 agonist]
NorEpi Elimination
MOA and COMTβ> urine
NorEpi Indication
Acute hypOtension due to VASODILATORY shock
DOPAMINE TRADE NAME
DOPAMINE ;-)
DOPAMINE HALF-LIFE
2-3 MIN
DOPAMINE MOA
DOPAMINE MOA: [General Beta Agonist] + [SOME alpha agonist activity]
DOPAMINE ELIMINATION
MOA AND COMT
DOPAMINE INDICATION
Cardiogenic Shock
IsoProterenol Half-life
short
IsoProterenol
MOA
[General Beta Agonist]
IsoProterenol Elimination
COMT β> Urine
IsoProterenol INDICATIONS (2)
IsoProterenol 1) Transient Heart Block 2) Bronchospasm during Anesthesia
DoButamine HALF-LIFE
2-3 MIN
DoButamine MOA
[MOSTLY Beta 1 AGONIST] ; some beta 2 activity
DoButamine ELIMINATION
COMTβ> Urine
DoButamine INDICATION
Short term for INC cardiac contractility
DoButamine TOXICITY
Hypotension (from vasoDilation;Beta 2 activity)
IsoProterenol TOXICITY
Tachyarrhythmias
DOPAMINE Toxicity (2)
-Low BP -Ischemia
Norepi TOXICITY (2)
- Ischemia - NE Extravasation (IV) β> Use [PhenTolamine as antidote]
EPININEPHRINE TOXICITY
ARRHYTHMIAS
NorEPINEPHRINE -CO? -TPR? -HR? -OVERALL MAP?
NorEPINEPHRINE Physiological effects: ΒΊIncreased CO; ΒΊincrease TPR; ΒΊdecrease HR (baroreflex); ΒΊoverall increased MAP
DOPAMINE LOW DOSE: _____ TPR/ _______ CO; vs. HIGH DOSE: ______ TPR and _____ MAP
DOPAMINE LOW DOSE: decreased TPR/ increased CO; vs. HIGH DOSE: Increased MAP and TPR
IsoProterenol Physiological effects -TPR? -CO? -MAP? -Broncho____(constricts/dilates)
IsoProterenol Physiological effects: Decreased TPR; Increased CO; Small decrease in MAP; bronchodilation
DOBUTAMINE Physiological effects -CO? -inotropic vs. chronotropic?
DOBUTAMINE Physiological effects: Increased CO -MORE INOTROPIC due to [LOW INVOLVEMENT OF baroreceptor reflex which would normally INC chronotropic effects from compensation to hypOtension]`
TERBUTALINE Physiological effects -Broncho____(constricts/dilates) -Uterine contraction vs. relaxation?
TERBUTALINE Physiological effects: Bronchodilation; Uterine relaxation
TERBUTALINE Toxicity (3)
TERBUTALINE Toxicity: Tachycardia; Muscle tremor; Tolerance
TERBUTALINE MOA
TERBUTALINE [BETA TWO AGONIST]
TERBUTALINE INDICATIONS
TERBUTALINE Prevent and Reverse Bronchospasm in [Asthma/Bronchitis/Emphysema] Pts
ALBUTEROL MOA
[BETA TWO AGONIST]
ALBUTEROL INDICATION
Bronchial Smooth Muscle Relaxation
PHENYLEPHRINE Physiological effects: -TPR? -MAP? -HR? -PUPIL? -BRONCHIOLE SECRETION?
PHENYLEPHRINE Physiological effects: Increased TPR and MAP; decreased HR (baroreflex); Pupillary dilation; decrease bronchiole and sinus secretions.
PHENYLEPHRINE HALF-LIFE
[less than 1 hour] - metabolizes slowly because it is NOT degraded by [Plasma COMT]
PHENYLEPHRINE Mechanism of Action
[alpha 1 AGONIST]
PHENYLEPHRINE ELIMINATION
MAO
PHENYLEPHRINE Indication (4)
-PRESSOR during Anesthesia -Nasal Congestion -Dilate Pupils for Eye Exam (mydriatic agent) -SVT
PHENYLEPHRINE Toxicity
HTN
PHENYLEPHRINE: Can Cause ____[INC/DEC] in HR due to _____ ______
PHENYLEPHRINE: Can cause DEC in HR due to [Baroreceptor Reflex] when peripheral vasoconstriction is initiated
CLONIDINE MOA
[alpha TWO AGONIST]
CLONIDINE ELIMINATION
Urinated Out
CLONIDINE INDICATION (2)
β’HTN β’Analgesia
CLONIDINE TOXICITY
CLONIDINE Toxicity: (x) Dry Mouth (x) HTN Crisis if withdrawn after Chronic Usage
CLONIDINE Works by _____[INC/DEC] Peripheral vasoconstriction CENTRALLY but will have some _____[INC/DEC] Peripheral vasoconstriction by acting directly in the ______
CLONIDINE Works by DECREASING Peripheral vasoconstriction CENTRALLY (inhibits sympathetics) but will have SOME INC peripheral vasoconstriction by acting directly in the PERIPHERY/ BODY
AMPHETAMINE Physiological effects: -TPR? -Inotropic vs. Chronotropic? -MAP?
AMPHETAMINE Physiological effects: ΒΊIncreased TPR/diastolic BP ΒΊPositive inotropic and Positive chronotropic effects; ΒΊ increased MAP pressure
AMPHETAMINE MOA
AMPHETAMINE MOA: [Indirect sympathoMimetic] - Causes NorEpi Release
AMPHETAMINE INDICATION (3)
ADHD / narcolepsy / [nasal congestion]
AMPHETAMINE Toxicity (4)
AMPHETAMINE Toxicity: (x) Tachycardia (x) HTN (x) Anxiety (x) tyramine accumulation if patient has taken MAO inhibitor within the previous 2 weeks is why MAO inhibitors are CONTRAINDICATED w/Amphetamine βββββββββββββββββββββββββββ- βT.H.A.t Amphetamine is TOXICβ
AMPHETAMINE is an _______ Agent
AMPHETAMINE is an Anorexic Agent
PARTIAL BETA AGONIST Examples (1)
-Pindolol
PARTIAL BETA AGONIST Mechanism: Treats HTN effectively when HTN is secondary to________. [Partial Beta Agonist] work by reducing _______ binding. They will still INC HR/Contractility BUT NOT AS MUCH AS _______ and since it prevents _______, the baseline HR/Contractility actually goes down from where it was initially **Is used for pts who canβt tolerate _______ very well with traditional [_______ _______ blockers]
PARTIAL BETA RECEPTOR AGONIST Mechanism: Treats HTN effectively when HTN is secondary to [HIGH Sympathetics]. [Partial Beta Agonist] work by reducing [NOrEPI/EPI] binding. Pindolol will still INC HR/Contractility BUT NOT AS MUCH AS NOrEPI/EPI and since it prevents NOREPI/EPI, the baseline HR/Contractility actually goes down from where it was initially **Is used for pts who canβt tolerate bradycardia very well with traditional [Cardioselective beta blockers]
PARTIAL BETA AGONIST -HR? -Heart Contractility? -Renin Release?
PARTIAL BETA RECEPTOR AGONIST CV Effects (These CV Effects are most manifested when Sympathetics is the original cause) *DEC HR *DEC Heart Contractility *DEC Renin Release
PARTIAL BETA RECEPTOR AGONIST USES (1)
HTN (for pt less tolerant to bradycardia/reduced exercise capacity)
PARTIAL BETA RECEPTOR AGONIST TOXICITY (5)
Toxicity are the same as the [NON-SELECTIVE BETA BLOCKERS] (1) Bronchospasm (2) mask symptoms of hypoglycemia (3) CNS effects including insomnia and depression (4) can raise triglycerides (5) bradycardia
PARTIAL BETA RECEPTOR AGONIST Contraindications (2)
*2nd/3rd Degree heart Block *Cardiogenic Shock
ALPHA ADRENERGIC RECEPTOR BLOCKER EXAMPLES (2)
ALPHA ADRENERGIC RECEPTOR BLOCKER *[iRReversible Phenoxybenazmine] *[REVERSIBLE PHENTOLAMINE]
ALPHA ADRENERGIC RECEPTOR BLOCKER CV Effects (3)
ALPHA ADRENERGIC RECEPTOR BLOCKER 1. Prevents vasoconstrictionβ> DEC BPβ>but will cause reflex INC in NorEpi release 2. INC inotropy and INC Chronotropy due to blocking the [a2 pre-synaptic receptor] β> Release of NorEpi @ nerve terminals 3. will unmasks vasodilatory effect of Epi
ALPHA ADRENERGIC RECEPTOR BLOCKER USES (2)
*perioperative tx of pheochromocytoma *Dermal Necrosis
GENERAL ALPHA BLOCKER TOXICITY (3)
GENERAL ALPHA BLOCKER Toxicity: (x) Prolonged hypOtension (x) Reflex Tachycardia (x) Nasal Congestion βItβs TOXIC to give ur pt [General Alpha Blockerβs] PRNβ
ALPHA ADRENERGIC RECEPTOR BLOCKER Contraindications (1)
ALPHA ADRENERGIC RECEPTOR BLOCKER Contraindications: Pt with Coronary Artery Dz
ALPHA 1 RECEPTOR BLOCKER EXAMPLES (3)
ALPHA 1 RECEPTOR BLOCKER Examples: -Prazosin -Doxazosin - Terazosin
ALPHA 1 RECEPTOR BLOCKER CV Effects (2) *Prevents _______ *[Less HR INC / Contractility INC] than [NON-selctive alpha receptor blockers] because ____________. This ultimately DEC _______ release in the synaptic cleft and SA Node is not stimulated any further
ALPHA 1 RECEPTOR BLOCKER CV Effects: *Prevents Vasoconstriction *[Less HR INC / Contractility INC] than [NON-selctive alpha receptor blockers] since [alpha 2 receptor] on [pre-synpatic nerve terminal] IS STILL FUNCTIONAL and can still negatively feedback when NorEpi is releasedβ> ultimately DEC NorEpi release in the synaptic cleft and SA Node is not stimulated no further
ALPHA 1 RECEPTOR BLOCKER USES (2)
ALPHA 1 RECEPTOR BLOCKER ΒΊHTN ΒΊBenign Prostatic Hyperplasia
ALPHA 1 RECEPTOR BLOCKER TOXICITY (2)
ALPHA 1 RECEPTOR BLOCKER TOXICITY: (x) Syncope (x) Orthostatic hypOtension
Methylphenidate: MOA
Indirect sympathomimetic (increases NE and dopamine)
Methylphenidate: Indication
ADHD
Ephedrine: MOA
Indirect sympathomimetic
Ephedrine: Indication
Pressor agent with anesthesia
What main drugs make up the Amphetamine family ? (6)
- Amphetamine 2. Methamphetamine 3. Methylphenidate 4. Ephedrine 5. Pseudoephedrine 6. Tyramine
Pseudo-ephedrine: MOA
Indirect sympathomimetic
Pseudo-ephedrine: Indication
Nasal decongestion
Tyramine: MOA
Displaces NE
Tyramine: Half-life
Normally very short
Tyramine: Indications
Not therapeutic
Tyramine: Elimination
MAO
Propanolol: MOA
General (non-selective) Beta Blocker
Propanolol: Indications (3)
- Hypertension 2. Angina due to atherosclerosis 3. MI
Timolol: MOA
General (non-selective) Beta Blocker
Timolol: Indications
Glaucoma
Nadolol: Half-life
20-24 hrs
Nadolol: MOA
General (non-selective) Beta-blocker
Nadolol: Indications (2)
- Long-term angina 2. Hypertension
What are the Non-selective Beta-blockers? (3)
Propanolol, nadolol, timolol
Cardiovascular effects of Non-selective Beta-blockers? (3)
- Reduced heart rate 2. Reduced contractility 3. Reduced vasoconstriction (as a result of reduced RENIN release)
Effect of Non-selective Beta-blockers on bronchioles? (1)
Can cause bronchiole constriction in those with asthma or COPD.
Non-selective Beta-blockers: Toxicity (5)
- Bronchospasm 2. Bradycardia 3. CNS effects (insomnia/depression) 4. MASK sx of hypOglycemia 5. Triglyceride INC βββββββββββββββββββββββββββ- β(General) B Blockers Can Modulate Triglycerides β
Non-selective Beta-blockers: Contraindications (4)
- Heart Block 2. Sinus bradycardia 3. Bronchial Asthma 4. Cardiogenic shock β[He Should Be Careful] w/General Beta Blockersβ
LIST THE 5 Drugs Eliminated by COMT
βCOMT d.i.N.e.D on 5 Drugsβ 1. doButamine 2. isoProterenol 3. NOREPI [MAO and COMT] 4 epi 5. DOPAMINE [MAO and COMT]