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Flashcards in Adrenergic Antagonists Deck (14):
1

List the conditions that are most commonly treated with B-blockers. What is the mechanism by which B-blockers produce their beneficial effects?

use: HTN, (angina, arrhythmia)
mechanisms
- cardioselective (B1 blockers)
- nonselective (B1 and B2 blockers)
- partial agonists (B1 and B2 agonists)

2

Identify the 6 beta-adrenergic antagonists and the commonly recognized category of beta-blockers to which they belong.

NONSELECTIVE
- propranolol
- timolol
- nadolol

CARDIOSELECTIVE
- atenolol
- metoprolol

PARTIAL AGONISTS
- pindolol

3

Describe how toxic side effects of the beta antagonist drugs differ with their receptor subtype selectivity.

NONSELECTIVE
- bronchospasm
- symptoms of hypoglycemia
- raise triglycerides
- bradycardia

CARDIOSELECTIVE (B1)
- hypotension
- bradycardia
- mild, transient

PARTIAL AGONISTS
- same as non-selective

4

List the 5 prominent alpha-adrenergic antagonists. Identify the following for each:
- receptor subtype selectivity
- conditions they are used for

NON-SELECTIVE
- phenoxybenzamine (irreversible)
- phentolamine (reversible)
=> USE: HTN in relation to perioperative tx of pheochromocytoma, dermal necrosis, vasoconstrictor extravasation

A1 SELECTIVE
- prazosin
- doxazosin
- terazosin
=> USE: HTN, benign prostatic hyperplasia

5

List the most serious side effects produced by selective and non-selective alpha-adrenergic receptor antagonists.

NONSELECTIVE: prolonged hypotension, reflex tachycardia
SELECTIVE A1: orthostatic hypotension

6

Explain why selective alpha-1-adrenergic receptor antagonists are more preferable for use in hypertension than non-selective alpha-adrenergic receptor antagonists.

because there is less cardiac stimulation b/c A2 functions are preserved

7

Describe the following for non-selective beta antagonists:
- drug names
- effects
- use
- toxicity
- contraindications

NAMES: propranolol, nadolol, timolol

EFFECTS
- reduced heart rate and contractility
- reduced renin release
- reduced vasoconstriction
- bronchiole constriction in patients with asthma or COPD

USE
- HTN
- angina
- glaucoma
- heart failure
- arrhythmia

TOXICITY
- bronchospasm
- hypoglycemia
- increased triglycerides
- bradycardia

CONTRAINDICATIONS
- side effects in patients with respiratory diseases
- asthma
- sinus bradycardia
- heart block
- cardiogenic shock

8

Describe the following for cardioselective beta antagonists:
- drug names
- effects
- use
- toxicity
- contraindications

NAME: atenolol, metoprolol, esmolol (reduced respiratory side effects)

EFFECT
- reduced heart rate and contractility
- reduced renin release

USE
- HTN
- angina
- arrhythmia (only esmolol; only transient b/c short half-life)

TOXICITY
- mild, transient
- hypotension
- bradycardia

CONTRAINDICATIONS
- sinus bradycardia
- heart block
- cardiogenic shock

9

Describe the following for partial beta agonists:
- drug names
- effects
- use
- toxicity
- contraindications

NAME: pindolol

EFFECT
- reduced heart rate and contractility
- reduced renin release
- reduced vasoconstriction
- bronchiole constriction in patients with asthma or COPD

USE
- when HTN is due to sympathetic output
- in those less tolerant of bradycardia
- in those with less tolerance for exercise

TOXICITY
- less bradycardic effect
- bronchospasm
- hypoglycemia
- increased triglycerides

CONTRAINDICATION
- asthma
- sinus bradycardia
- heart block
- cardiogenic shock

10

If you have a patient with respiratory disease, what beta blocker category would you recommend?

cardioselective: atenolol, esmolol, metoprolol
non-selective and partial agonists will still have respiratory issue

11

If you have a patient that has bradycardia, which beta blocker category would you recommend?

- partial agonists b/c have less bradycardic effect

12

If you have a patient with high sympathetic output, which beta blocker category would you recommend?

- partial agonists b/c block high output

13

Describe the following for non-selective alpha antagonists:
- drug names
- effects
- use
- toxicity
- contraindications

NAMES
- phenoxybenzamine
- phentolamine

EFFECTS
- inhibit vasoconstriction
- block presynaptic A2 receptor => increased NT release => increased ionotropy and cronotropy => increased CO and contractility
- vasodilation

USE
- HTN associated with perioperative pheochromocytoma
- dermal necrosis
- vasoconstrictor extravasation

TOXICITY
- prolonged hypotension
- reflex tachycardia

CONTRAINDICATIONS
- CAD

14

Describe the following for selective A1 antagonists:
- drug names
- effects
- use
- toxicity
- contraindications

NAME
- prazosin
- doxazocin
- terazocin

EFFECTS
- inhibit vasoconstriction
- preserves A2 function

USE
- HTN
- benign prostatic hyperplasia

TOXICITY
- orthostatic hypOtension
CONTRAINDICATIONS