Alpha-Adrenoceptor Antagonists (Alpha-blockers)

Question 1

What do the alpha-blockers treat?

Answer 1

Hypertension

Pheochromocytoma

Benign prostate hypertrophy

Question 2

Where are the alpha-receptors located?

Answer 2

Vascular smooth muscle

Nerve terminals

Question 3

Activation of the alpha receptor causes what?

Answer 3

Vasoconstriction (Thus blocking the receptor can reduce hypertension)

Question 4

Where are alpha 1 receptors found?

Answer 4

Vascular smooth muscle

Question 5

Where are alpha 2 receptors found?

Answer 5

Nerve terminals

Question 6

T/F. Alpha-blockers are front line agents to treat hypertension.

Answer 6

False

Question 7

What are the two broad categories of alpha-blockers?

Answer 7

Competitive and non-competitive (irreversible)

Question 8

What is the difference between a competitive and a non-competitive alpha-blocker?

Answer 8

Competitive blockers CAN be overcome by increasing concentration.

Question 9

Phenoxygenzamine

Answer 9

Irreversible, alpha 1 blocker

Rarely used

Treats pheochromocytoma and acute HT

Question 10

Phentolamine

Answer 10

Competitive, alpha blocker (non-selective)

Treats pheochromocytoma and acute HT

Question 11

Prazosin

Answer 11

Competitive, alpha-1 blocker

Commonly used to treat BPH and HTaa

Question 12

T/F. -osin at the end of a drug means it is an alpha-1 blocker.

Answer 12

True

Question 13

What is a common adverse effect of alpha-blockers?

Answer 13

Postural hypotension