PHARM: Erectile Dysfunction

Question 1

What is the only drug for erectile dysfunction that is not oral?

Answer 1

alprostadil

Question 2

What is the ROA of alprostadil?

Answer 2

Either intra-
urethral suppository placed there to dissolve in residual urine and
to be absorbed across the urethral wall. The other option is by
direct injection onto the corpus cavernosum, taking care to avoid
the top or bottom of the penis.

Question 3

What is the PGE1 synthetic mimic used for erectile dysfunction?

Answer 3

Alprostadil

Question 4

What are the PDE-5 inhibitors used for erectile dysfunction?

Answer 4

Avanafil
Sildenafil
Tadalafil
Vardenafil

Question 5

What hormone replacement therapies are used for erectile dysfunction?

Answer 5

Methyltestosterone

Testosterone

Question 6

What is the alpha-2 receptor antagonist used for erectile dysfunction?

Answer 6

Yohimbine

Question 7

What is the short-acting selective alpha-1 blocker used for erectile dysfunction?

Answer 7

Alfuzosin

Question 8

MOA: Activates adenylate cyclase, which synthesizes cAMP from ATP. cAMP acts as a second messenger activating protein kinase A, which results in an efflux of intracellular calcium and subsequent smooth-muscle relaxation and erection.

Answer 8

alprostadil

Question 9

MOA: Decrease the breakdown of cGMP by inhibition of PDE5, resulting in the prolonged high levels of cGMP necessary for erections.

Answer 9

Avanafil
Sildenafil
Tadalafil
Vardenafil

Question 10

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

Answer 10

alfuzosin

Question 11

What are the two main mechanisms by which yohimbine decreases intracellular calcium to relax penile smooth muscle?

Answer 11

• Antagonizes the stimulation of alpha2-ARs by NE released from adrenergic nerve terminals
• Antagonizes the presynaptic inhibition of the Non-Adrenergic Non-Cholinergic nerves and increases the release of NO, which stimulates soluble guanylate cyclase to synthesize cGMP

Question 12

Why does alprostadil have very few CV side effects?

Answer 12

delivery options for alprostadil allows for avoidance of systemic drug effects

Question 13

How quickly does alprostadil work?

Answer 13

). Action occurs fast (minutes) and has a durable effect (30 min to several hours).

Question 14

What are the most common adverse effects of alprostadil?

Answer 14

Penile, urethral and testicular pain

Question 15

What is the most common adverse effect of PDE-5 inhibitors?

Answer 15

headache

Question 16

What are the common serous toxicities of PDE-5 inhibitors?

Answer 16

cardiovascular issues, sudden loss of hearing and sight

Question 17

What drug class is contraindicated with PDE-5 inhibitors?

Answer 17

ORGANIC NITRATES! Both agents would produce vasodilation, albeit by different mechanisms, leading to severe and life-threatening hypotension!

Question 18

What other drugs may interact with PDE-5 inhibitors?

Answer 18

alpha blockers (increase hypotension) and drugs affecting CYP activity

Question 19

Which PDE-5 is most likely to elicit QT prolongation with concurrent meds?

Answer 19

Vardenafil has interactions with over 70 drugs—making it the most likely to produce QT prolongation→ cardiac arrhythmia!

Question 20

Testosterone may be used with what drug to enhance its effect?

Answer 20

improve the response of hypogonadal men to PDE5 inhibitors like sildenafil citrate

Question 21

TRUE or FALSE, yohinbine crosses the BBB easily?

Answer 21

TRUE– leads to anxiety, antidiuresis, dizziness, flushing, HA, HTN, increased motor activity, irritability, nervousness or restlessness, sinus tachycardia, tremor

Question 22

At supra-clinical doses, what actions does yohimbine have?

Answer 22

MAOI actions

Question 23

In what patients is yohimbine contraindicated?

Answer 23

Patients with renal failure or dysfunction