BPH and ED Pharm

Question 1

What are the male lower urinary tract symptoms (LUDS)?

Answer 1

• interrupted/weak stream
• frequency
• hesitation
• fullness
• dribbling
• urgency

Question 2

How do a1-adrenergic receptor antagonists relieve LUDS?

Answer 2

they compete with NE, causing smooth muscle contraction in the prostate

• reduce spasm, promote muscle relaxation
• rapid relief of symptoms seen in days

Question 3

terazosin MOA?

adverse effects?

drug interactions?

Answer 3

a1»»>a2, is not uroselective

postural hypotension, dizziness, fatigue

PDE-5 inhibitors (sildenafil, vardenafil)

Question 4

doxazosin MOA?

adverse effects?

drug interactions?

Answer 4

a1»»>a2, not uruselective

postural hypotension, dizziness, fatigue

PDE-5 inhibitors (sildenafil, vardenafil)

Question 5

alfuzosin MOA?

adverse effects?

drug interactions?

Answer 5

non-specific a1 selective, functionally uroselective

QT prolongation

PDE-5 inhibitors, increase the concentration of CYP 34A substrates

Question 6

tamsulosin MOA?

adverse effects?

drug interaction?

Answer 6

a1A=a1D>a1B. a1A and a1D are uroselective

reduced ejaculation, intraoperative floppy iris synd (IFIS)

PDE-5 inhibitors, increases concentration of CYP 34A substrates

Question 7

solidosin MOA?

adverse effects?

drug interaction?

Answer 7

a1A=a1D>a1B. a1A and a1D are uroselective

reduced ejaculation, intraoperative floppy iris synd (IFIS)

PDE-5 inhibitors, increases concentration of CYP 34A substrates

Question 8

What effect does androgen metabolism in prostate epithelial cells have on prostate enlargement during BPH?

Answer 8

androgenic steroids, T and DHT enable prostate epithelium survival and growth

Question 9

How does the mechanism of action of steroid 5a-reductase inhibitor relate to BPH?

Answer 9

• • steroid 5a-reductase types 1 and 2 convert serum T -> DHT in cells**
• DHT “starvation” causes epithelial atrophy, shrinkage and gradual relief of LUTS

Question 10

Why are a1-adrenergic receptor antagonists a dynamic remedy in the treatment of BPH?

Answer 10

they are antagonists, that work in multiple different ways to treat BPH
- they relax certain muscles and keep blood vessels open, some being uroselective

Question 11

Why are steroid 5a-reductase inhibitors considered a structural remedy in the treatment of BPH?

Answer 11

they are structural inhibitors, not antagonists

• • FInasteride = more speciFIc **
• inhibits SAR-2 (more specific to prostate)
• 70% decrease in serum DHT
• • DUasteride = DUal inhibitor **
• inhibits both SAR-1/2
• 90% decrease in serum DHT

Question 12

sildenafil (Viagra)

• duration of action?
• onset?

Answer 12

competitive inhibitor of PDE-5, must take on empty stomach

• 4 hours
• 60 mins

Question 13

vardenafil (Levitra)

• duration of action?
• onset?

Answer 13

competitive inhibitor of PDE-5, must take on empty stomach

• 4-5 hours
• 60 minutes

Question 14

tadalafil (Cialis)

• duration of action?
• onset?

Answer 14

competitive inhibitor of PDE-5

• • 36 hours, half life=18 hours! ***
• 60 mins

Question 15

avanafil MOA

• duration of action?
• onset?

Answer 15

competitive inhibitor of PDE-5

• 4 hours
• high dose= 15 mins, normal dose=30 mins*

Question 16

Why are PDE-5 inhibitors contraindicated in patients taking organic nitrates for angina pectoris?

Answer 16

PDE-5 inhibitors are vasodilators, and when taken together with nitrates (which increase the amount of NO), it can cause extreme and dangerous hypotension

Question 17

Why is priapism considered a medical emergency? What are the treatment options?

Answer 17

pooling blood will begin to coagulate, needs to be evacuated

- can result in permanent corporal fibrosis and ED!**

Question 18

What are alternative treatments to PDE-5 for ED?

Answer 18

• vacuum erection devices

- penile injections with alprostadil (Caverject)

Question 19

What is the difference in MOA of alprostadil and PDE-5 inhibitors?

Answer 19

alprostadil is a PGE1 agonist (rather than a PDE-5 inhibitor)

PGE1 -> more adenylate cyclase -> increase in cAMP -> erection