Endocrine: Sex Hormone Kinetics and Unique Features

Question 1

How log is treatment of GnRH Antagonists (cetorelix) to achieve gonadotropin suppression?

Answer 1

4-5 days

Question 2

How long does it take a GnRH agonist (leuprolide) to achieve gonadotropin suppression?

Answer 2

3 weeks

Question 3

When starting a long-acting GnRH agonist with prostate cancer, why must an antiandrogen be co-administered?

Answer 3

Agonist causes LH surge, must suppress effects to suppress tumor growth

Question 4

estrogens are conjugated in the ______ and excreted in_____

Answer 4

conjugated in liver

excreted in bile

Question 5

What reverses estrogen conjugation and increases its bioavailability?

Answer 5

Enterohepatic circulation

Question 6

Estrogens and progesterone are/aren’t orally active…

Answer 6

aren’t

Question 7

This progestin has progesterone and androgenic activity…

Answer 7

19-nortestosterones

Question 8

mifepristone antagonizes both the progesterone receptor and the…

Answer 8

GC receptor

Question 9

are progestin-only mini pills more or less effective than combo oral contraceptives?

Answer 9

less effective

Question 10

long-term progestin therapy causes breakthrough bleeding when?

Answer 10

early

Question 11

Thromboembolic and blood clotting disorders are severe side effects of synthetic estrogens, this risk is much higher in what patient population?

Answer 11

smokers over 35

Question 12

oral contraceptives may decrease effectiveness of…

Answer 12

anticoags, anticonvulsants, TCAs, guanethidine and PO hypoglycemic agents

Question 13

What two classes may reduce the effectiveness of oral contraceptives?

Answer 13

abx and microsomal enzyme inducers

Question 14

For HRT, why are progestins added to estrogen replacement?

Answer 14

to prevent endometrial hyperplasia