Flashcards in Repro - Pharmacology Deck (53)
What are the mechanisms of Leuprolide?
GnRH analog with agonist properties when used in pulsatile fashion; Antagonist properties when used in continuous fashion (downregulates GnRH receptor in pituitary => low FSH/LH); Think: "LEUprolide can be used in LIEU of GnRH"
What are 4 clinical uses for Leuprolide? Specify its form/context of use in each case.
(1) Infertility (pulsatile) (2) Prostate cancer (continuous - use with flutamide) (3) Uterine fibroids (continuous) (4) Precocious puberty (continous)
In what way is Leuprolide given to treat prostate cancer? With what other drug is it combined for this treatment?
Prostate cancer (continuous - use with flutamide)
What are 3 toxicities of Leuprolide?
(1) Antiandrogen (2) Nausea (3) Vomiting
What are 3 examples of drugs used as Estrogens?
Estrogens (ethinyl estradiol, DES, mestranol)
Again, what are 3 examples of Estrogens? What is their mechanism?
Estrogens (ethinyl estradiol, DES, mestranol); Bind estrogen receptors
What are 3 clinical uses for Estrogens (ethinyl estradiol, DES, mestranol) in women? What is a clinical use for these drugs in men?
Hypogonadism or ovarian failure, Menstrual abnormalities, HRT in postmenopausal women; Use in men with androgen-dependent prostate cancer
What are 4 toxicities of Estrogens? What are 2 contraindications of Estrogens?
(1) Increased risk of endometrial cancer (2) Bleeding in postmenopausal women (3) Clear cell adenocarcinoma of vagina in females exposed to DES in utero (4) Increased risk of thrombi; Contraindications- ER + breast cancer, History of DVTs
What are 3 examples of selective estrogen receptor modulators (SERMs)?
(1) Clomiphene (2) Tamoxifen (3) Raloxifene
Where does Clomiphene act, and what is its mechanism?
Antagonist at estrogen receptors in hypothalamus. Prevents normal feedback inhibiton and increases release of LH and FSH from pituitary, which stimulates ovulation.
In what context is Clomiphene used clinically? Give a prominent example of this context.
Used to treat infertility due to anovulation (e.g., PCOS)
What are 4 side effects associated with Clomiphene?
May cause (1) hot flashes, (2) ovarian enlargement, (3) multiple simultaneous pregnancies, and (4) visual disturbances.
What kind of drug is Tamoxifen? What are its mechanisms, and where does it act?
Selective Estrogen Receptor Modulator (SERM); Antagonist on breast tissue; Agonist at uterus, bone
What are 2 complications/toxicities associated with Tamoxifen use?
Associated with endometrial cancer, thromboembolic events
How is Tamoxifen primarily used clinically?
Primarily used to treat and prevent recurrence of ER + breast cancer
What kind of drug is Raloxifene? What are its mechanisms, and where does it act?
Selective Estrogen Receptor Modulator (SERM); Agonist on bone; Antagonist at uterus
What side effect/complicaion is associated with Raloxifene use? What other SERM shares this same risk?
Inreased risk of thromboembolic events; Tamoxifene
How is Raloxifene used clinically, and why?
Decrease resorption of bone => used to treat osteoporosis
What are 2 uses for hormone replacement therapy?
Used for relief or prevention of menopausal symptoms (e.g., hot flashes, vaginal atrophy) and osteoporosis (increase estrogen, decrease osteoclast activity)
What risk does estrogren replacement therapy (ERT) increase? How is this risk managed?
Unopposed estrogen replacement therapy (ERT) increases the risk of endometrial cancer, so progesterone is added.
Besides endometrial cancer, what other risk may possibly be increased by ERT?
Possible cardiovascular risk
What other drug functions like Anastrozole? What is their mechanism? How are they used clinically?
Anastozole/Exemestane; Aromatase inhibitors used in postmenopausal women with breast cancer
What are the mechanism and effects of Progestins?
Bind progesterone receptors, decreasing growth and increasing vascularization of endometrium
What are 3 clinical uses for Progestins?
Used in (1) oral contraceptives and in the treatment of (2) endometrial cancer and (3) abnormal uterine bleeding
What is another name for Mifepristone?
What is the mechanism of Mifepristone (RU-486)?
Competitive inhibitor of progestins at progesterone receptors
What is the clinical use of Mifepristone (RU-486)? With what other drug is it administered?
Termination of pregnancy. Administered with misoprostol (PGE1)
What are 3 toxicities associated with Mifepristone (RU-486)?
(1) Heavy bleeding, (2) GI effects (nausea, vomiting, anorexia), (3) Abdominal pain
What 2 drugs are used for oral contraception? What are their shared mechanism and effects?
Oral contraception (synthetic progestins, estrogen); Estrogen and progestins inhibit LH/FSH and thus prevent estrogen surge. No estrogen surge => no LH surge => no ovulation.