Repro - Pharmacology

Question 1

What effect do GnRH agonists have on the reproductive HPA axis?

Answer 1

GnRH agonists are stimulatory if given as pulses, inhibitory if given continuously

Question 2

What effect does anastrozole have on the female HPA axis?

Answer 2

It is an aromatase inhibitor that prevents estrogen formation from androgens

Question 3

What is the mechanism of action and result of finasteride administration?

Answer 3

It is an reductase inhibitor that blocks the conversion of testosterone to dihydrotestosterone

Question 4

How do the clinical uses of leuprolide differ depending on the way in which it is administered?

Answer 4

Leuprolide is a gonadotropin-releasing hormone agonist when dosed in a pulsatile fashion and a gonadotropin-releasing hormone antagonist when dosed continuously

Question 5

What adverse effects are associated with leuprolide use?

Answer 5

Antiandrogenic actions, nausea, and vomiting

Question 6

Name three common clinical uses for leuprolide.

Answer 6

Infertility (pulsatile), prostate cancer (continuous, used with flutamide), and uterine fibroids

Question 7

Is leuprolide dosed in a pulsatile or continuous fashion for the treatment of prostate cancer? Why?

Answer 7

Leuprolide is given continuously to inhibit gonadotropin-releasing hormone; this decreases circulating androgens that can stimulate prostate adenocarcinoma

Question 8

How can testosterone be used to treat hormonal deficiencies?

Answer 8

Administration of testosterone can be used in hypogonadism and to help develop secondary sexual characteristics

Question 9

What is the role of testosterone in patients who have suffered from a burn?

Answer 9

Testosterone stimulates anabolism, which helps promote recovery from burns or other severe injuries

Question 10

What role can testosterone play in the treatment of a malignancy generally seen in women?

Answer 10

Testosterone can be used to treat estrogen receptor-positive breast cancer

Question 11

What genital exam finding would you expect in a male using exogenous testosterone?

Answer 11

Testicular atrophy; because exogenous testosterone blocks the release of luteinizing hormone, intratesticular testosterone will decrease, causing testicular atrophy

Question 12

How would exogenous testosterone affect the height of a child that has not completed puberty?

Answer 12

This child may be shorter than expected because of premature closure of the epiphyseal plates

Question 13

What serum lipid panel findings would you expect in a patient who has been taking testosterone?

Answer 13

Elevated low-density lipoprotein and decreased high-density lipoprotein

Question 14

What is the mechanism of action of finasteride?

Answer 14

Finasteride is a reductase inhibitor, which blocks the conversion of testosterone to the more potent dihydrotestosterone

Question 15

What is the mechanism of action of flutamide?

Answer 15

Competitive testosterone receptor antagonist

Question 16

Name two drugs that function as antiandrogens as an additional effect of their interference with steroid signaling.

Answer 16

Ketoconazole (an antifungal) blocks desmolase, decreasing steroid synthesis; spironolactone (a diuretic) blocks steroid binding

Question 17

What are two adverse effects common to both ketoconazole and spironolactone?

Answer 17

Gynecomastia and amenorrhea

Question 18

Flutamide is used to treat what condition?

Answer 18

Prostate carcinoma

Question 19

What antiandrogenic drugs can be used to treat the hirsutism associated with polycystic ovarian syndrome?

Answer 19

Ketoconazole or spironolactone

Question 20

What are the mechanisms of action of ethinyl estradiol, diethylstilbestrol, and mestranol?

Answer 20

Binding to estrogen receptors and acting as agonists

Question 21

Name four conditions in women that are treated with estrogens.

Answer 21

Hypogonadism, ovarian failure, menstrual abnormalities; and as hormone replacement therapy in postmenopausal women

Question 22

Name a condition in elderly men that can be treated with estrogens

Answer 22

Androgen-dependent prostate cancer

Question 23

What are the adverse effects of treatment with exogenous estrogens?

Answer 23

An increased risk of endometrial carcinoma, abnormal uterine bleeding in postmenopausal women, and hypercoagulability

Question 24

You diagnose a woman with clear-cell adenocarcinoma of the vagina; what should you ask about in her history?

Answer 24

In utero exposure to diethylstilbestrol

Question 25

Name two conditions that are contraindications to estrogen therapy.

Answer 25

Estrogen receptor-positive breast cancer and a history of deep vein thrombosis

Question 26

How does the interaction of clomiphene at the hypothalamus result in an increase in ovulation?

Answer 26

Clomiphene is a partial estrogen receptor agonist at the hypothalamus, blocking negative feedback on luteinizing hormone and follicle-stimulating hormone; elevated follicle-stimulating hormone and luteinizing hormone cause increased ovulation

Question 27

What are two primary clinical uses for clomiphene?

Answer 27

The treatment of infertility and polycystic ovarian syndrome

Question 28

What are four adverse effects associated with clomiphene use?

Answer 28

Hot flashes, ovarian enlargement, multiple simultaneous pregnancies, and visual disturbances

Question 29

How is tamoxifen used in breast cancer?

Answer 29

Because it acts as an estrogen antagonist in the breast, it is used to treat and prevent recurrences of breast cancer in estrogen receptor-positive tumors

Question 30

Which selective estrogen receptor modulator reduces the resorption of bone and is used to treat osteoporosis?

Answer 30

Raloxifene; it acts as an estrogen receptor agonist in bones

Question 31

What are indications for hormone replacement therapy?

Answer 31

Menopausal symptoms (eg, hot flashes, vaginal atrophy) and osteoporosis that is caused by decreased estrogen levels

Question 32

In hormone replacement therapy, unopposed estrogen can increase the risk of what disease?

Answer 32

Endometrial cancer; it also may increase the risk of cardiovascular events

Question 33

Why is progesterone added to hormone replacement therapy?

Answer 33

To reduce the risk of endometrial cancer

Question 34

What is the mechanism of action of anastrozole and exemestane?

Answer 34

Anastrozole and exemestane function by inhibiting aromatase, the enzyme that converts androgens to estrogens

Question 35

In what clinical scenario are anastrozole and exemestane used?

Answer 35

In postmenopausal women with hormone-responsive breast cancer

Question 36

What effect do progestins have on the endometrium?

Answer 36

Upon binding the progesterone receptor, they reduce the growth of the endometrial lining while increasing its vascularization

Question 37

Name three clinical uses of progestins.

Answer 37

In oral contraceptive pills, to treat endometrial cancer, and to treat abnormal uterine bleeding

Question 38

What is the mechanism of action of mifepristone (RU-486)?

Answer 38

It is a competitive inhibitor of progestins at progesterone receptors

Question 39

What is the primary clinical use of mifepristone?

Answer 39

Termination of pregnancy in conjunction with the administration of misoprostol (PGE1)

Question 40

What are the known toxicities of mifepristone?

Answer 40

Heavy bleeding, gastrointestinal effects (nausea, vomiting, anorexia), and abdominal pain

Question 41

How reliable are oral contraceptive pills in the prevention of pregnancy?

Answer 41

They are very reliable (<1% failure when used correctly) but must be taken daily to be effective

Question 42

What is the effect of oral contraceptive pills on malignancy?

Answer 42

Women taking oral contraceptive pills have lower rates of endometrial and ovarian cancer

Question 43

A woman who takes oral contraceptive pills asks you about her risk for ectopic pregnancy; what is the relationship between the two?

Answer 43

Oral contraceptive pills decrease the risk of ectopic pregnancy (and pregnancy in general)

Question 44

Name six systemic adverse effects of oral contraceptive pills.

Answer 44

Elevated triglycerides, hypertension, depression, weight gain, nausea, and hypercoagulability

Question 45

How do oral contraceptive pills work?

Answer 45

They work by preventing an estrogen surge and thus the luteinizing hormone surge that causes ovulation

Question 46

Dinoprostone is an analogue of what molecule?

Answer 46

PGE2

Question 47

How is dinoprostone used in pregnancy?

Answer 47

Dinoprostone causes cervical dilation and uterine contractions, inducing labor

Question 48

What is the role of ritodrine and terbutaline during labor?

Answer 48

These are β2-agonists, which relax the uterus and reduce contractions (remember: ritodrine allows the fetus to "return to dreams" by stopping premature labor)

Question 49

What is the mechanism of action of tamsulosin?

Answer 49

Tamsulosin is an α1-receptor agonist used to treat benign prostatic hyperplasia

Question 50

Why does tamsulosin relax the smooth muscles of the prostate but not the systemic vasculature?

Answer 50

It is selective for α1AD-receptors found on the prostate, rather than the α1B-receptors on systemic vessels

Question 51

What is the primary clinical use for sildenafil and vardenafil?

Answer 51

The treatment of erectile dysfunction (remember: sildenafil and vardenafil fill the penis)

Question 52

A patient presents with symptoms of flushing, reflux, headache, and blue-green vision; what drug has he likely ingested?

Answer 52

Sildenafil or vardenafil (remember: Hot and sweaty, but then Headache, Heartburn, Hypotension)

Question 53

Sildenafil and vardenafil should not be used in patients taking what other class of drug?

Answer 53

Nitrates; the concomitant use can precipitate life-threatening hypotension

Question 54

How do sildenafil and vardenafil cause the increase of penile blood flow and resultant erection?

Answer 54

By inhibiting cGMP phosphodiesterase, there is an increase in cGMP resulting in increased nitric oxide and smooth muscle relaxation in the corpus cavernosum