Pharm of androgens - french

Question 1

T is the most important androgen in ____ and _____

Answer 1

muscle and liver

95% synth in testes
5% in adrenals

*Hypogonadal if

Question 2

Finasteride (597)

Answer 2

a 5a-reductase inhibitor
- decrease conversion of T to DHT

• Useful in Benign prostatic hypertrophy (BPH) and male pattern baldness

Question 3

How is estrogen made in males?

Answer 3

Synthesized from T via C19 aromatase which is expressed in testes, bone, brain, adipose tissue

Question 4

Most significant action of E in males?

Answer 4

Occurs in bone

1. closure of epiphyseal plate
   - unfort. if adolescent male abuse E
2. Males w/o aromatase or E receptors –> epiphyses do not fuse and long bone growth continues
3. Osteoporotic

Question 5

When would you use T hormone replacement therapy in elders?

Answer 5

1. T

Question 6

When would you use T hormone replacement therapy in aging men?

Answer 6

Only in mend with T

Question 7

Would you give T for impaired spermatogenesis?

Answer 7

No
Only indicated for T deficiency

T suppression of gonadotropin secretion would FURTHER impair spermatogenesis

Question 8

Which route of T admin gives most stable plasma T levels thru-out dosing interval?

Answer 8

transdermal gel
-give every 24 hours

Tradeoff: maintain stable T level throughout dosing (maintain mood, E, libido)
but MOST expensive

Question 9

Parenteral T

Answer 9

T ethanate

T cypionate

*Tradeoff: less frequent injections, but greater fluctuations in serum T levels

Question 10

Oral T

Answer 10

Methyltestosterone

Tradeoff:
excellent oral absorptions, but rapid hepatic degradation

Question 11

How does T result in decreased spermatogenesis?

Answer 11

1. Decreased LH/FSH (neg feedback)
2. Conversion of androgens to estrogens

*return to nl fxn after discontinuation

Question 12

Does androgen use result in anemia? What about increase risk to arterial thrombosis?

Answer 12

No
T has erythropoietic fx and HCT goes up

But you DO have increased susceptibility to arterial thrombosis
(low HDL, high LDL, Increased platelet aggregation)

Question 13

Anti or pro androgen?

1. GnRH antagonist
2. Pulsatile admin of GnRH
3. Continuous admin of GnRH

Answer 13

1. GnRH antagonist
   - Anti: w/ competitive inhib
2. Pulsatile admin of GnRH
   - Pro: stimulation by increasing LH and FSH release from pituitary
3. Continuous admin of GnRH
   - Anti: neg inhibition with receptor down regulation/desensitization
   (prior to desen ~ 1 week, LH/FSH will transiently increase with surge in T)

Question 14

Flutamide and Spirinolacton target what?

Answer 14

Androgen receptors and inhibit androgen (steroid) binding

Question 15

Tx of Polycystic ovarian syndrome

Answer 15

1st line: estrogen-progestin contraceptive

2. Spirinolactone
   - inhibit androgen binding
   or Ketoconazole

Question 16

Tx of benign prostatic hyperplasia

Answer 16

5 a reductase inhibitors

• Finasteride
• Dutasteride

Question 17

Tx of male pattern baldness (androgenic alopecia)

Answer 17

finasteride

a 5a reductase inhibitor

Question 18

Bicalutamide and Leuprolide are usually given together for the tx of prostate cancer

Answer 18

Leuprolide: GnRH agonist

• will initially increase LH + FSH –> INcrease in T
• But then desensitization kicks in

Bicalutamide: #1 androgen R blocker
- needed in conjunction with Leupromide to prevent initial Increase in T w/ leupromide

Question 19

Adverse effects of Leuprolide

Answer 19

hypogonadism

Question 20

Adverse effects of finasteride-dutasteride

Answer 20

decreased libido

ejaculatory ED

Question 21

Adverse effects of bicalutamide

Answer 21

androgen deprivation effects (loss of libido, gynecomastia)

Question 22

Adverse effects of spirinolactone

Answer 22

gynecomastia

Question 23

Benign prostatic hypertrophy (BPH) can be characterized by frequent urinary urgency, diminished urinary stream ect. Which of the following best describes how an a1-adrenergic antagonist improves urinary flow?

Answer 23

Decreases the resistance of urethral sphincter

note that relaxation of detrusor muscle of bladder is used to tx overactive bladder