Sympatholytics

Question 1

What are the 4 side effects of a1 antagonists?

Answer 1

• orthostatic hypotension
• inhibition of ejaculation
• nasal stuffiness
• tachycardia

Question 2

what are the 2 a-adrenergic antagonists that treat pheochromocytoma and hypertensive crisis?

Answer 2

Phenoxybenzamine (oral)
Phentolamine (parenteral)

Question 3

what are the 2 a1 adrenergic antagonists that treat hypertension and benign prostatic hypertrophy?

Answer 3

*oral
Terazosin
Doxazosin

Question 4

Phenoxybenzamine (dibenzyline)

Answer 4

**nonselective
- also blocks ACh, histamine, and serotonin receptors
- irreversible antagonist resulting from covalent modification of receptor

Question 5

Phentolamine (regitine)

Answer 5

**nonselective a
- competitive, reversible blocker
- potent vasodilator, but induces pronounced reflex tachycardia
- block presynaptic a2 receptors may promote release of NE
- also blocks 5-HT receptors and is a muscarine receptor agonist

Question 6

a1 adrenergic receptor antagonists (-zosin)

Answer 6

quinazolines
- vary in half life
prazosin = 3 hrs
terazosin = 12 hrs
doxazosin = 20 hrs
- undergo extensive metabolism, excreted in bile
- vasodilators
- relaxation of smooth muscle in enlarged prostate and in bladder
- first dose effect

Question 7

a1A antagonist (tamsulosin)

Answer 7

• very selective to prostate urethra (a1A)
• less prone to induce fall in BP

Question 8

what are the 4 non-selective beta adrenergic antagonists?

Answer 8

• propranolol
• nadolol
• timolol
• cartelol

Question 9

propranolol (inderal)

Answer 9

• lipophilic
• local anesthetic properties
• blockade is activity dependent

Question 10

what are the pharmacological effects of propranolol? (5)

Answer 10

• decreased cardiac output + HR
• reduced renin release
• inc VLDL
• inhibit lipolysis + glycogenolysis
• inc bronchial airway resistance

Question 11

What are the therapeutic uses for beta-adrenergic antagonists? (8)

Answer 11

• hypertension
• angina
• cardiac arrythmias
• migraine
• stage fright
• thyrotoxicosis
• glaucoma
• congestive heart failure

Question 12

Nadolol (corgard)

Answer 12

• less lipophilic than propranolol
• long half life (~20 hrs)
• mostly excreted unchanged in urine
  administration: oral
  uses: hypertension, angina, migraine

Question 13

Timolol (timoptic)

Answer 13

• thiadiazole nucleus with morpholine ring
  administration: oral, ophthalmic
  uses: hypertension, angina, migraine, glaucoma

Question 14

Carteolol (cartrol)

Answer 14

• possesses intrinsic sympathomimetic activity (ISA)
• partial agonist
• less likely to cause bradycardia and lipid abnormalities
  administration: oral, ophthalmic
  uses: hypertension, glaucoma

Question 15

Metoprolol/Bisoprolol

Answer 15

• cardioselective
• less bronchoconstriction
• moderate lipophilicity
  half life: metoprolol -> 3-4 hrs, bisoprolol -> 9-12hrs
• significant first pass metabolism
  administration: oral, parenteral
  uses: hypertension, angina, antiarrhythmic, congestive heart failure

Question 16

what are the 5 B1 selective antagonists

Answer 16

• metoprolol
• bisoprolol
• atenolol
• esmolol
• nebivolol

Question 17

Atenolol (tenormin)

Answer 17

• cardioselective
• less bronchoconstriction
• low lipophilicity
  half-life: 6-9 hrs
  administration: oral, parenteral
  uses: hypertension, angina

Question 18

Esmolol (brevibloc)

Answer 18

• very short acting
  half life: 9 min
• rapid hydrolysis by esterases found in RBCs
  administration: parenteral
  uses: supraventricular tachycardia, atrial fibrillation, perioperative hypertension

Question 19

Nebivolol (bystolic)

Answer 19

• low lipid solubility
• vasodilation due to nitric oxide production
• hypertension

Question 20

what are the 5 side effects of beta-blockers?

Answer 20

• bradycardia
• AV block
• sedation
• mask sx of hypoglycemia
• withdrawal sx

Question 21

What are the 3 contraindications for beta blockers?

Answer 21

• asthma
• COPD
• congestive heart failure

Question 22

what are the 2 mixed adrenergic antagonists?

Answer 22

• labetalol
• carvedilol

Question 23

Labetalol (normodyne, trandate)

Answer 23

• nonselective B + a1 antagonist
  (1R, 1’R) = beta blocking activity
  (1S, 1’R) = a1 blocking activity
• beta blocking prevents reflex tachycardia normally associated with a1 antagonists
  administration: oral, parenteral
  uses: hypertension, hypertensive crisis

Question 24

Carvedilol (coreg)

Answer 24

• nonselective B + a1 antagonist
• both enantiomers antagonize a1 receptors
• only (s) enantiomer has beta blocking activity
  administered: oral
  uses: hypertension, congestive heart failure