Beta-Blockers

Question 1

MOA of BB w/ no ISA

Answer 1

decrease HR and contractility–> Decrease CO

inhibit renin release (EXCEPT Pindolol)

Decrease central sympathetic outflow (except for those w/ low lipid solubility)

Decrease release of peripheral NE by inhibiting presynaptic beta adrenergic receptors

Question 2

Pindolol

Answer 2

does not inhibit decrease renin release

High ISA, some MSA, no cardioselectivity, lipid soluble

Question 3

Utility of BB w/ no ISA

Answer 3

Especially useful in pts w/ high renin level HTN

Question 4

Effects of BBs w/ no ISA

Answer 4

w/ chronic use…

decrease CO and peripheral resistance and arterial pressure

Question 5

Clinical uses of 1st and 2nd generation B-blockers in HTN

Answer 5

effective therapy for all grades of HTN

Question 6

Clinical uses of 1st and 2nd generation B-blockers in HTN…

More effective in…

Answer 6

High renin HTN

young and caucasian

Question 7

Clinical uses of 1st and 2nd generation B-blockers in HTN:

Less effective in…

Answer 7

Low renin HTN

elderly and AA

Question 8

BBs and diuretics

Answer 8

BBs do not cause H20 and salt retention
–so can be administered w/out diuretic

But has additive antihypertensive effect when administered w/ diuretic

Question 9

Highly preferred in hypertensive pts w/…

Answer 9

MI
ischemic heart disease
HF
hyperthyroidism
migraines

Question 10

CHF

Answer 10

3rd generation BBs
carvedilol
metaprolol-XL
bisoprolol

Question 11

MI

Answer 11

useful in preventing 2nd MI

perhaps b/c of bradycardia?

Question 12

Other indications

Answer 12

Sinus and AV arrhythmias
open angle glaucoma
anxiety

Question 13

Propranolol uses

Answer 13

Non-selective BB that produces resting bradycardia and decrease HR during exercise –> hypotension

membrane stabilizing activity: antiarrhythmic

produces bronchospasm; contraindicated in asthmatics

slow withdrawal of drug to prevent reflex tachycardia

Question 14

Metoprolol and Atenolol

Answer 14

50-100-fold more selective in blocking β1-adrenergic receptors

“Cardioselective agents”

Question 15

Bisoprolol

Answer 15

Long-acting drug (take once a day

significantly decreases all case mortality

glaucoma eyedrops

Question 16

PIndolol and acebutolol

Answer 16

Non-selective drugs with partial agonist activity.

Decrease CO and HR less than other drugs.

Question 17

Esmolol

Answer 17

ARRHYTHMIAS!!!

Selective drug w/ VERY short half-life

Given IV for management of tachycardia, arrhythmias during surgery and postoperative tachycardia caused by halothane anesthetic

Question 18

Timolol

Answer 18

non-selective drug

eye-drops for Rx of chronic open angle glaucoma

Question 19

Side effects

Answer 19

Cold extremities

Bradycardia

Bronchospasm (avoid ALL drugs w/ asthma; permitted w/ COPD)

CNS side effects

Metabolic

Drug withdrawal syndrome

fatigue, decreased exercise tolerance, impotence

Question 20

Cold extremities side effect

Answer 20

• -Unopposed α adrenergic action constricts BV in the skin and limits blood flow causing cold extremities.
• -Prolonged use worsens peripheral arterial insufficiency; Raynaud’s phenomenon.

Question 21

Bradycardia side effect

Answer 21

Decreased AV nodal conduction; contraindicated with verapamil
and diltiazem

Question 22

Metabolic side effects

Answer 22

• Block glycogenolysis and delay recovery from hypoglycemia in type 1 diabetics (seen with non-selective drugs but less frequently with ß1-selective agents).
• Block HSL in adipocytes and increase LDL and reduce HDL and increase triglycerides.

Question 23

Drug withdrawal syndrome

Answer 23

Prolonged drug use upregulates β-receptors in the heart.

Abrupt withdrawal causes tachycardia; withdraw slowly!!!!

Question 24

3rd Generations:

Labetalol

Answer 24

non-selective beta + a1 antagonist

given IV for HTN emergencies

Question 25

3rd Generations: | Carvedilol

Answer 25

non-selective β + α1-receptor antagonist By blocking α1-AR, CO maintained with increased fall in peripheral resistance. * Antioxidant; binds and scavenges ROS * Protects membranes from lipid peroxidation. Prevents LDL oxidation and decreases LDL uptake into coronary blood vessels. * Primarily used for CHF & HTN; decreased mortality and morbidity in pts w/ mild to moderate CHF * PO; extensively protein bound; hepatic (2D6) metabolism

Question 26

3rd Generations; | Celiprolol

Answer 26

Cardio-selective + beta2 agonism Directly vasodilates BV due to partial ß2- agonist activity. Used for treatment of HTN and angina.

Question 27

3rd Generations | Nebivolol

Answer 27

drugs w/ NO mediated vasodilation Highly β1 selective; devoid of ISA, membrane stabilizing activities, and α1 blocking activities. * Has antioxidant activity/neutral to favorable effects on both carb and lipid metabolism. * decreased BP by decreasing HR and peripheral vascular resistance. * Significantly increases stroke volume, maintains CO and systemic blood flow. * Drug of choice for HTN with metabolic syndrome!!!

Question 28

Propanolol

Answer 28

MSA, lipid soluble

Question 29

Metoprolol

Answer 29

some MSA, cardioselective, lipid soluble

Question 30

Atenolol

Answer 30

cardioselective, NOT lipid soluble

Question 31

Timolol

Answer 31

some ISA, lipid soluble