Gonadal Hormones: Androgens Flashcards Preview

Pharm: Final Exam Drugs > Gonadal Hormones: Androgens > Flashcards

Flashcards in Gonadal Hormones: Androgens Deck (17)
Loading flashcards...
1
Q
What are the various androgens?
A
Testosterone: natural
Synthetic Androgens: 17 alkyl derivatives with increased anabolic effects:
Oxandrolone
Methyltestosterone
Stanozolol
Fluoxymesterone
Nandrolone
Oxymetholone
Danazol
2
Q
DHT: dihydrotestosterone is more potent than testosterone (testis) and androstenedione (Adrenal gland). What are some functions of testosterone and DHT?
A
Testosterone:
--Genitalia: development of penis, seminal vesicles, sperm, muscle mass and RBCs. Differentiation of epididymis, vas deferens, seminal vesicles. Libido and deepening of voice
DHT (dihydrotestosterone):
--differentiation of penis, scrotum and prostate
--prostate gland growth, balding and sebaceous gland activity
3
Q
Testosterone via 5 alpha reductase gets converted to Dihydroxy Testosterone, what are the effects of testosterone and DHT?
A
Testosterone: development of penis, seminal vesicles, sperm, muscle mass and RBCs
--differentiation of epididymis, vas deferens, seminal vesicles, libido, deepening of voice, closing epiphyseal plates
DHT: early: differentiation of penis, scrotum, and prostate and late: prostate gland, growth, balding sebaceous gland activity
4
Q
The drugs for androgens are what?
A
Androgens (Testosterone)
Antiandrogens
--receptor antagonists: flutamide
---5 alpha reductase inhibitor: Finasteride
---Synthesis inhibitors: ketoconazole
--GnRH agonists
5
Q
What are the clinical uses of Androgens?
A
Substitution therapy in hypogonadism
Increases bone density (prevents osteoporosis), could be used in increasing muscle mass
Some cases of aplastic anemia
Admin: transdermal, buccal, subcutaneous implant and IM
6
Q
What are the adverse effects of Androgens?
A
Over masculinization
In women: hirsutism, suppression of menses, acne and clitoral enlargement
Hepatic adenomas and prostatic hypertrophy
Cholestatic Jaundice (elevated serum transaminations)
Aggression and Dependency
Premature closure of epiphysis
illicit use in Athletes
--over dosage of androgens can result in feminization as a result of negative feedback inhibition and conversion of exogenous testosterone into estrogen
7
Q
The first drug is Danazol, what does this drug do?
A
Is an inhibitor of P450 in gonadal steroid synthesis
Its an androgen derivative, a partial agonist of progestin and glucocorticoid receptors
Used in endometriosis and fibrocystic disease of the breast
8
Q
What are AE of Danazol?
A
AE: hepatitis: abnormal liver function tests and drug interaction due to P450 inhibition
It is modified testosterone shows some signs of masculinizing effects: acne, hirsutism, menstrual disturbances
9
Q
What are the antiandrogen drugs?
A
Androgen Receptor Antagonists:
--Flutamide
--Bicalutamide
--Nilutamide
--Cyproterone
--Spironolactone
--Ketoconazole
10
Q
What androgen receptor blockers are used for androgen receptor positive cancers?
A
Flutamide: a substituted anilide
Bicalutamide
Nilutamide
Primarily used in conjunction with GnRH analogs
--Leuprolide (to decrease initial tumor flare ups of prostate cancer)
11
Q
How does Spiranolactone produce antiandrogen action?
A
Blocks aldosterone and competes with androgen receptors
--it is used in hirsutism
12
Q
How does Cyproterone produce antiandrogen action?
A
It has progesteronal effect suppresses LH and FSH. Used in hirsutism and to decrease excessive sexual drive in men
13
Q
What is ketoconazole used for?
A
Oral
Adrenal and Gonadal Steroid Synthesis Inhibitor
Use: in prostate cancer but not 1st line
AE: may have drug interactions with other steroids due to decrease P450
14
Q
The 5 alpha reductase inhibitor is Finasteride (Propecia), what are the uses and AE?
A
Oral
Inhibits conversion of testosterone to DHT
Use: BPH and promote hair growth
AE: gynecomastia, teratogenicity and impotence
15
Q
How do 5 alpha reductase inhibitors work in the treatment for BPH?
A
Finasteride and Dutasteride: act by reducing the size of the prostate gland
--tx for 6 to 12 months is generally needed before prostate size in sufficiently reduced to improve symptoms
Side Effects: decreased libido and ejaculatory or erectile dysfunction
16
Q
How do Alpha 1 adrenergic antagonists work in the treatment of BPH?
A
Terazosin, Doxazosin, Tamsulosin and Alfuzosin
--relieve outlet obstruction of the bladder by reducing the tension of prostatic smooth muscle in the prostate, prostate capsule, and bladder neck
AE: orthostatic hypotension and dizziness
17
Q
Combination therapy with an alpha adrenergic antagonist plus a 5 alpha reductase inhibitor produces what?
A
Greatest reduction in the symptoms of BPH, such as acute urinary retention, urinary incontinence, renal insufficiency or recurrent urinary tract infections