Adrenergic antagonists

Question 1

Phenoxybenzamine

Answer 1

Nonselective alpha antagonist
Irreversible - non-competitive
Alpha1 > alpha2

Blocks several other receptors, cross BBB
Blockade ends after new receptor synthesis

Vasodilation and reflex tachycardia (block a1 but increase NE via a2)

Nausea, vomiting and weakness

Question 2

Use of phenoxybenzamine

Answer 2

Pheochromocytoma
Peripheral vascular disease
Raynaud’s syndrome
Acrocyanosis

Question 3

Phentolamine

Like Tolazoline

Answer 3

Competitive alpha blocker
Rapid onset
Decrease BP
Enhance NE release
Stimulate GI and HCl/Pepsin release

Question 4

Phentolamine use

Answer 4

Pheochromocytoma
Clonidine withdrawal
Treat necrosis

SE: orthostatic hypotension

Question 5

Yohimbine

Answer 5

Alpha 2 and 5HT blocker

Improve male sexual function?

Question 6

Chlorpromazine, haloperidol

Answer 6

Block alpha1 and DA

Antipsychotic

Question 7

Ergotamine

Answer 7

Treat migraine HA

Question 8

Ergonovine

Answer 8

Treat postpartum hemorrhage

Question 9

Prazosin

Answer 9

Alpha 1 selective antagonist
Treat HTN without reflex tachycardia

Considerable syncope in patients

Question 10

Terazosin

Answer 10

HTN and BPH

Alpha 1 antagonist

Question 11

Doxazosin

Answer 11

HTN and BPH

Alpha 1 antagonist

Question 12

Tamulosin

Answer 12

Alpha1A subtype

BPH with little orthostatic hypotension

Question 13

Propranolol

Answer 13

Competitive beta blocker
Decrease HR, decrease exercise tolerance, decrease infarct
Slowly decreases peripheral resistance

**Caution with asthmatics and diabetics
May penetrate CNS - drowsiness

Question 14

Propranolol metabolism

Answer 14

Largely reduced by first pass

Question 15

Use of Beta blockers

Answer 15

Angina
Very helpful with CHF
HTN
HA
Arrhythmias
Pheochromocytoma
Hyperthryoid
Anxiety
MI, post MI

Question 16

Beta blocker sudden withdrawal

Answer 16

Angina, HTN, possible MI

Question 17

Beta blocker drug interactions

Answer 17

Hypotensive agents

Insulin (mask hypoglycemia)

Question 18

Nadolol

Answer 18

Longer lasting beta blocker

Question 19

Timolol

Answer 19

More potent beta blocker

HTN and glaucoma

Question 20

Metoprolol

Answer 20

Cardioselective beta blocker

Question 21

Atenolol

Answer 21

Cardioselective beta blocker

Question 22

Labetalol

Answer 22

Alpha 1 and beta receptors blocker

HTN and pheochromocytoma

Question 23

Carvedilol

Answer 23

Alpha 1 and beta blocker

**very helpful with CHF

Question 24

Pindolol

like carteolol

Answer 24

Reduces sympathetic tone on heart (compete with Epi and NE)

HTN

Question 25

Acebutolol

Answer 25

Cardioselective for beta1 blocker

HTN, dysrhythmias

Question 26

Betaxolol

Answer 26

Beta1 selective blocker

Glaucoma and HTN

Question 27

Bisoprolol

Answer 27

CHF

Question 28

Esmolol

Answer 28

Rapid onset and short acting selective beta1 blocker

Use around surgery
Still use cautiously with asthmatics

Question 29

Guanethidine

Answer 29

Uptake I - Displacement and release of NE - Blocks NE release

Does not enter CNS

Uncontrolled HTN

Question 30

Guanadrel

Answer 30

Like Guanethidine but more rapid and shorter duration

Question 31

Bretylium

Answer 31

Blocks NE

Antiarrhythmia

Question 32

Clonidine

Answer 32

Alpha 2 agonist
Can enter CNS and downregulate sympathetic
Initial increase in BP then decrease in BP

Treat opioid withdrawal

Question 33

Sudden clonidine withdrawal

Answer 33

HTN crises

Question 34

Methyldopoa

Answer 34

HTN in pregnant females

Question 35

Guanabenz

Answer 35

Like Clonidine but less useful