selective ESTROGEN RECEPTOR modulators → SERM's

Question 1

what is the definitions of “SERMs”?

Answer 1

mixed estrogen AGONISTS with estrogen effects in some tissues & partial agonists/antagonists in others

Question 2

the available SERMs: (drug names)

Answer 2

1. raloxifene
2. tamoxifen
3. toremifene
4. clomiphene
5. ospemifene

Question 3

raloxifene → mechanism of action:

Answer 3

1. partial estrogen AGONIST action in the bone → decreased resorption, increased density & decreased vertebral fractures → treatment of osteoporosis
2. competitive ANTAGONIST of estradiol at the estrogen receptor
3. no estrogenic effects in endometrial tissue

Question 4

tamoxifen → mechanism of action:

Answer 4

1. competitive ANTAGONIST of estradiol at the estrogen receptor (same as in raloxifene)
2. prevents growth of breast tissue → treatment of advanced breast cancer in postmenopausal women
3. acts as an AGONIST at endometrial receptors → causing hyperplasia & increasing the risk of endometrial cancer

Question 5

toremifene → mechanism of action:

Answer 5

1. inhibit growth of breast tissue

2. favorable pattern of lipids

Question 6

clomiphene → mechanism of action:

Answer 6

1. partial estrogen AGONIST
2. interfere with feedback of estrogens on hypothalamus → increase secretion of GnRH & gonadotropins → stimulate ovulation

Question 7

raloxifene → indications:

Answer 7

1. prophylaxis of breast cancer in high risk patients

2. prevention & treatment of osteoporosis in postmenopausal women

Question 8

tamoxifen → indications:

Answer 8

1. metastatic breast cancer
2. adjuvant therapy following mastectomy or radiation
3. prophylactic therapy to reduce risk of breast cancer in high-risk pat.

Question 9

clomiphene → indication:

Answer 9

infertility ass. with anovulatory cycles

Question 10

ospemifene → indication:

Answer 10

dyspareunia (= painful sexual intercourse due to medical or psychological causes)

Question 11

raloxifene → CONTRAindications:

Answer 11

1. past or active history of venous thromboembolic events

2. should not be used with cholestyramine (reduce absorption)

Question 12

tamoxifen → pharmacokinetics:

Answer 12

1. rapidly absorbed by oral administration
2. metabolized by P450
3. through bile → into feces

Question 13

tamoxifen → side effects:

Answer 13

1. hot flashes
2. nausea
3. drug interactions
4. increases risk of venous thrombosis

Question 14

clomiphene → side effects:

Answer 14

1. nausea
2. headache
3. vasomotor flushes
4. visual disturbances
5. ovarian enlargement
6. increase risk of multiple births