Male GU Pharmacology

Question 1

What are the three families of drugs to treat Benign Prostatic Hypertrophy?

Answer 1

A1 antagonists, steroid 5alpha reductase inhibitors, and PDE 5 inhibitors.

Question 2

What alpha1 subtype is more common on vascular, prostate smooth muscle, detrusor instability, and spinal cord for urinary function?

Answer 2

A1b > A1a, A1a, A1d>A1a, and A1d

Question 3

What subtype is terazosin and doxazosin selective for, and what are the 3 adverse effects?

Answer 3

A1 over A2. Postural hypotension, dizziness, and fatigue.

Question 4

What is the selectively for tamsulosin and silodosin? What are 2 adverse effects?

Answer 4

A1a=A1d>a1b.

Reduced ejaculation and IFIS.

Question 5

What is the selectively for Alfuzosin and what is the one adverse effect?

Answer 5

Non specific A1.

QT Prolongation.

Question 6

What is unique about alfuzosin and its selectivity?

Answer 6

It is uroselective, meaning it goes after A1 in the prostate far more than serum.

Question 7

Two big reasons why the prostate enlarges?

Answer 7

Age and too much dihydrotestosterone

Question 8

So, what is the problem with dihydrotestosterone and the prostate.

Answer 8

Testosterone and DHT cause the epi of the prostate to grow. Well DHT is way more potent than T. SAR converts T to DHT, so we inhibit SAR.

Question 9

What are the 4 effects of inhabiting SAR?

Answer 9

More T, less DHT, less androgen binding to receptor in prostate, less gene transcription inside prostate ep cells.

Question 10

SAR has two types, 1 and 2. The SAR inhibitors are finasteride and dunasteride. Which ones do they inhibit?

Answer 10

Finasteride inhibits 2 and dunasteride inhibits 1 and 2.

Question 11

Which SAR type is found more in BPH?

Answer 11

SAR 2

Question 12

Which drug decreases serum SAR more?

Answer 12

Dunasteride

Question 13

You should avoid alfuzosin for BPH in what patients?

Answer 13

Patients with liver impairment

Question 14

How long do SAR inhibitors take to begin having an effect?

Answer 14

About 3 months

Question 15

What treatment do you use if there are severe symptoms of BPH or the prostate is just massive?

Answer 15

Combo A1 antagonist and SAR inhibitor

Question 16

What drug to use if the patient has BPH and erectile dysfunction?

Answer 16

Tadalafil

Question 17

What is the simple and easy pathway to an erection he gives?

Answer 17

Nitric oxide leads to lots of cGMP which decreases calcium and leads to smooth muscle relaxation and erection.

Question 18

What is the onset of action for sild, vard, and tadalafil? What is the onset for avanafil?

Answer 18

Take one hour before.

Take 15 minutes before for high dose. Take 30 minutes before for normal dose.

Question 19

What is the duration of action for sild, vard, and Ava? What is the duration of action for tadalafil?

Answer 19

4. 36

Question 20

What is the MAO for these PDE 5 inhibitors?

Answer 20

Stop PDE5 from converting cGMP to GMP so you have more cGMP around to lower the calcium.

Question 21

What is an adverse effect for sildenafil, vardenafil, and avanafil and why?

Answer 21

Vision problems because they have some specificity for PDE6 receptor in the retina.

Question 22

2 contraindications for using PDE5 inhibitors?

Answer 22

Do not use with nitrates (severe hypotension) and do not use with A1 antagonists for BPH.

Question 23

Besides PDE5 antagonists, what other drug family do we use to treat erectile dysfunction?

Answer 23

PGE1 agonist

Question 24

Quickly explain the pathway with PGE leading to an erection and the MOA for a PGE agonist?

Answer 24

PGE leads to adenylate cyclase which increases cAMP which lowers intracellular calcium, relaxing smooth muscle and getting an erection. So, the PGE agonist stimulates this process.

Question 25

What is the adverse effect with Alprostadil, the PEG agonist, and how do you treat it?

Answer 25

Prolonged erection. Phenylephrine.