Adrenergics:β adrenergic receptor antagonists

Question 1

Minor actions of B adrenergic recpetor antagonists

Answer 1

partial agonists (i.e., activate β receptors partially in the absence of catecholamines; however, the intrinsic activities of these drugs are much less thana full agonist);

• local anesthetic or quinidine-like activity
• block α1 receptors
• vasodilating properties

Question 2

Non-Subtype-Selective β Adrenergic Receptor Antagonists known as

Answer 2

(“First Generation”)

Question 3

Prototype B adrenergic receptor antagonists

Answer 3

Propranolol

Question 4

Propranolol works by:

Answer 4

Competitive reversible blockade of both β1 and β2 receptors

Question 5

Propranolol works on B1, B2, both receptors

Answer 5

both

Question 6

Propranolol is used for:

Answer 6

Hypertension -
Angina -
Certain cardiac arrhythmias due to excess catecholamines or that respond to a
reduction in heart rate/AV conduction velocity
- Acute myocardial infarction
- Pheochromocytoma (adrenal tumor =excess NE
- Migraine prophylaxis

Question 7

Side effects of propranolol on
HR
Airway
sugars
others

Answer 7

Side Effects

• Cardiac depression, bradycardia/heart block
• May increase airway resistance
• Mask symptoms of hypoglycemia
• Sedation, impotence, nightmares

Question 8

A patient has asthma and congestive heart failure. is propranonolol safe?

Answer 8

Use with caution in patients with:

Question 9

If a patient has bradyarrhythmias, AV block or hypotension, are we safe to prescribe propranolol?

Answer 9

prescribe propranolol with caution, may exacerbate those

Question 10

What drug should we be wary of when prescribing heart meds to individual with insulin-dependent diabetes?

Answer 10

Propranolol

insulin-dependent diabetes prone to hypoglycemic episodes

Question 11

supersensitivity to β adrenergic stimulation which may cause angina, arrhythmias, or infarction could be caused by

Answer 11

Withdrawal syndrome from propranolol

Question 12

Timolol (Timoptic®) is:

Answer 12

non-selective β receptor antagonist

Question 13

Therapeutic use of timolol

Answer 13

angina/hypertension/pherochromocytoma/ arrythmias d/t excess catecholamines/ acute myocardial infarction
same as propranolol

Question 14

widely used in the treatment of wide angle glaucoma

Answer 14

Timolol

Question 15

How does timolol help with wide angle glaucoma

Answer 15

• decreases aqueous humor formation by ciliary epithelium leading to decreased intraocular pressure

Question 16

What affect does timolol have on pupil size and accomidation?

Answer 16

• does not affect pupil size or accommodation and is devoid of blurred vision and night blindness seen with miotics

Question 17

What is the benefit to a pt with wide angle glaucoma to systemic installation of Timolol?

Answer 17

• small amounts can be absorbed systemically after installation in eye; use with caution in patients with cardiac disease

Question 18

β1 – Selective Adrenergic Receptor Antagonists

Answer 18

(“Second Generation”)

Question 19

Prototype 2nd generation drug

Answer 19

– Metoprolol (Lopressor®)

Question 20

(“Second Generation”)

Answer 20

β1 – Selective Adrenergic Receptor Antagonists

Question 21

Major pharmacological actions of Metoprolol

Answer 21

• Competitive, reversible β1 receptor blocker

- at low doses is more selective at blocking the β1 receptor (~10-fold selective)

Question 22

What dose is metoprolol best as selectively blocking the B1 receptor

Answer 22

low dose… 10 fold more selecive

Question 23

Metoprolol is a
reversible/non-reversible
competitive/non-competitive
B1/B2 receptor blocker

Answer 23

competitive
reversible
B1

Question 24

Metoprolol has same therapeutic effects as:

Answer 24

propranolol

Question 25

treat heart failure only three β blockers tested in clinical studies and proven to slow rate of heart failure progression and to increase survival time

Answer 25

(metoprolol,carvedilol, bisoprolol)

Question 26

For Metoprolol the side effects are similar to propranolol except....

Answer 26

- less bronchoconstriction at lower doses

Question 27

Atenolol is orally active: dosing is:

Answer 27

once a day

Question 28

Does atenolol penetrate the CNS

Answer 28

does not penetrate into the CNS -- less CNS side effects -

Question 29

What do we use atenolol for?

Answer 29

therapeutic use: similar to propranolol (except for migraine prophylaxis)

Question 30

Atenolol is:

Answer 30

B1 antagonist

Question 31

β receptor antagonists with additional cardiovascular effects

Answer 31

(“Third Generation”)

Question 32

“Third Generation” drugs include

Answer 32

Labetalol | Carvedilol

Question 33

competitive antagonist of α1 receptor and both β receptors (non-selective) - therapeutic use: essential hypertension (oral) and hypertensive emergencies (IV)

Answer 33

Labetalol

Question 34

therapeutic use: essential hypertension (oral) and hypertensive emergencies (IV)

Answer 34

Labetalol

Question 35

competitive antagonist of α1 receptor and both β receptors (non-selective) - also has anti-oxidant properties and anti-inflammatory effects - blocks L-type calcium channels at higher doses

Answer 35

Carvedilol (Coreg®) -

Question 36

therapeutic use: chronic heart failure, hypertension, and acute MI

Answer 36

Carvedilol

Question 37

Carvedilol is a competitive antagonist of :

Answer 37

α1 receptor and both β receptors (non-selective)

Question 38

at higher doses, carvedilol will:

Answer 38

blocks L-type calcium channels