PHARM: BPH

Question 1

List the short-acting selective alpha-1 blockers.

Answer 1

Prazosin

Alfuzosin

Question 2

List the long-acting selective alpha-1 blockers

Answer 2

Terazosin

Doxazosin

Question 3

List the alpha-1a partially selective blockers

Answer 3

Tamsulosin

Silodosin

Question 4

List the PDE-5 inhibitor used for BPH

Answer 4

Tadalafil

Question 5

List the type 2 specific 5-alpha reductase inhibitor

Answer 5

Finasteride

Question 6

List the 5-alpha reductase inhibitor that acts on type 1 and type 2

Answer 6

Dutasteride

Question 7

Why is tadalafil used in BPH while other drugs in its class are not?

Answer 7

Has a really long duration of action (>35 hr) compared to other drugs in class

Question 8

How do alpha-1 blockers work?

Answer 8

Cause relaxation of the smooth muscle in the prostatic and penile urethra, thereby permitting easier urination.

Question 9

How is NO produced?

Answer 9

produced by the enzyme NOS is released from endothelial cells and cavernous nerves

Question 10

What is the action of NO?

Answer 10

stimulates guanylyl cyclase, resulting in increased levels of cGMP.

Question 11

What does cGMP do in cells?

Answer 11

activates protein kinase G

Question 12

What does protein kinase G do?

Answer 12

phosphorylates cellular membrane proteins to result in efflux of calcium and smooth muscle relaxation

Question 13

How do PDE-5 inhibitors work?

Answer 13

decrease breakdown of cGMP resulting in the prolonged high levels of cGMP necessary for erections and helps BPH symptoms by relaxing smooth muscle

Question 14

What is 5-alpha reductase?

Answer 14

enzyme that catalyzes the conversion of testosterone to DHT

Question 15

Where is type 2 5-alpha reductase found?

Answer 15

in prostate (can stimulate the DHT needed to drive proliferation of the prostate)

Question 16

Why is prazosin not a popular choice for an alpha-1 blocker?

Answer 16

half life is 2-4 hours—need for Q12h dosing and dose titration—NOT POPULAR

Question 17

Where is alpha-1a located in the human body?

Answer 17

predominant in the normal human prostatic stroma and lower urinary tract

Question 18

In what patients are alpha-1a inhibitors advantageous?

Answer 18

Normotensive: decreased necessity for dose titration (diminished effects on CV function)

Question 19

What are some disadvantages of alpha-1a specific inhibitors?

Answer 19

retrograde ejaculation (more with silodosin than tamsulosin) and block of dopamine and other regulatory CNS transmitter

Question 20

What is a strange adverse effect of alpha-1 blockers?

Answer 20

is floppy iris syndrome in patients undergoing cataract surgery

Question 21

What do alpha-1 blockers do to blood pressure?

Answer 21

DROP IT

Question 22

TOXICITY: HA, nausea, nasopharyngitis, URT symptoms or rarely non-arteritic ischemic optic neuropathy, retinal artery occlusion or hearing loss

Answer 22

TAdalafil

Question 23

TOXICITY: category X; ejaculation dysfunction; erectile dysfunction; decreased libido; gynecomastia

Answer 23

5-alpha reductase inhibitors
Finasteride
Dutasteride

Question 24

Why do 5-alpha reductase inhibitors make it difficult to monitor for prostate cancer?

Answer 24

decreases PSA levels

Question 25

Where are beta-sitosterols from?

Answer 25

South African Star Grass

Question 26

Are beta-sitosterols effective?

Answer 26

yes (symptomatic relief but do not shrink prostate)

Question 27

Does saw palmetto work for BPH patients?

Answer 27

NO