chapter 16: Adrenergic Antagonist

Question 1

adrenergic blockers

Answer 1

Block effects of adrenergic neurotransmitter

Drug that is antagonistic to or inhibits the transmission of nerve impulses in the SNS

Block alpha and/or beta receptor sites
Directly: by occupying receptors
Indirectly: by inhibiting release of neurotransmitters epinephrine and norepinephrine

Question 2

effects of adrenergic blockade

Answer 2

PNS preveils
See cholinergic s/sx
Can block NE release by stimulating A2 receptors centrally
A1, B1, B2 blockers work at the receptor site

Question 3

A1 blockers

Answer 3

Prazosin (Minipress)
Terazosin
Doxazosin (Cardura)
Tamsulosin (Flomax)

Block a response at the alpha adrenergic receptor site in the BV -prevent vasoconsriction and prostate constriction
Selective (Alpha 1 only)
Non-selective (Alpha 1 & Alpha 2)
Promote vasodilation = decrease BP

Use; HTN, BPH, pheochromocytoma, Raynaud’s

SE: Orthostatic hyportension, HA, dizziness, reflex tachycardia, nasal congestion, inhibition of ejaculation (10-20%)

Question 4

Prescribing considerations for A1 blockers

Answer 4

Therapeutic Goal: Manage HTN and reduce symptoms of BPH*
Baseline Data: HR, BP, Assess BPH symptoms
Teach orthostatic hypotension
Not first choice for HTN tx for older adults

Question 5

B bockers

Answer 5

Non selective-Blocks both beta 1 and beta 2 receptors
Causes decreased BP and pulse along with bronchoconstriction

Selective -Blocks beta1 only
Decrease BP and Pulse

MOA: Reduce HR, reduce force of contraction, reduce impulse through AV node. BC of this BB are useful in many CV disorders

Use: Angina (Mainstay tx for angina rt decrease cardiac workload -> decrease O2 demand), HTN ( not 1st line), Cardiac Dysrhythmias (common in tachy), MI (Decrease pain, infarction size in MI –decrease mortality and risk for infarction. Long term tx for MI pt.), HF,
Hyperthyroidism, Migraine prophylaxis, Performance anxiety, Pheochromocytoma, Glaucoma (decrease IOP), prevent tremor

SE: Bradycardia
Decreased CO, Precipitation of HF, AV heart block, tachycardia (if withdrawn abruptly)
(B2 blockade)- Bronchoconstriction, Hypoglycemia

Question 6

BB groups

Answer 6

3 Groups:
First Generation ( nonselective) propranolol Blocks B1 and B2
Second Generation (cardio selective) metoprolol Blocks B1
Third Generation (vasodilating) carvedilol

Question 7

propronolol (inderal)

Answer 7

Non selective BB

Use: HTN, angina dysrhythmias, MI
Migraine prophylaxis, hyperthyroidism, tremor

SE: B1 and B2 blocking Symptoms
Bradycardia, AV Block, HF, Bronchoconstriction, Inhibition of glycogenolysis, CNS Effects -pass thru BBB

Question 8

metoprolol (lopressor)

Answer 8

Routes: PO, IV

MOA: Selectively blocks (antagonizes) beta -1 adrenergic receptors (Cardio-Selective)

Uses: To manage HTN, angina, MI, dysrhythmias (tachycardia)

SE: Bradycardia, hypotension, dizziness, hypoglycemia, sexual dysfunction, SOB on exertion