Reproductive Pharmacology Flashcards
Reproductive Pharmacology
Leuprolide
MOA: GnRH analog with agonist properties when used in pulsatile fashion, antagonist properties when used in continuous fashion (downregulates GnRH receptor in pituitary) → ↓ FSH/LH
Use: Uterine fibroids, endometriosis, precocious puberty, prostate cancer, infertility
Reproductive Pharmacology
Estrogens (ethinyl estradiol, DES, mestranol)
MOA: Bind estrogen receptors
Use: Hypogonadism or ovarian failure, menstrual abnormalities, hormone replacement therapy in postmenopausal women; use in men with androgen-dependent prostate cancer.
Adverse Effects: ↑ risk of endometrial cancer, bleeding in postmenopausal women clear cell adenocarcinoma of vagina in females exposed to DES in utero, ↑ risk of thrombi.
Contraindications: ER ⨁ breast cancer, history of DVTs
Reproductive Pharmacology
Clomiphene
MOA: Selective estrogen receptor modulator. Antagonist at estrogen receptors in the hypothalamus. Prevents normal feedback inhibition and ↑ release of LH & FSH in from pituitary, which stimulates ovulation.
Use: Infertility due to anovulation.
Adverse Effects: Hot flashes, ovarian enlargement, multiple simultaneous pregnancies, visual disturbances.
Reproductive Pharmacology
Tamoxifen
MOA: Selective estrogen receptor modulator. Antagonist at breast; agonist at bone, uters
Use: Treat and prevent recurrence of ER/PR ⨁ breast cancer
Adverse Effects: ↑ risk of thromboembolic events and endometrial cancer.
Reproductive Pharmacology
Raloxifene
MOA: Selective estrogen receptor modulator. Antagonist at breast, uterus; agonist at bone.
Use: Osteoporosis
Adverse Effects: ↑ risk of thromboembolic events but no increased risk of endometrial cancer
Reproductive Pharmacology
Aromatase inhibitors (anastrozole, letrozole, exemstane)
MOA: Inhibit peripheral conversion of androgens to estrogens
Use: ER ⨁ breast cancer in postmenopausal women
Reproductive Pharmacology
Progestins (levonorgestrol, medroxyprogesterone, etonogestrel, norethindrone, megestrol)
MOA: Bind progesterone receptors, ↓ growth and ↑ vascularization of endometrium, thicken cervical mucus.
Use: Contraception, endometrial cancer, abnormal uterine bleeding.
Progestin challenge: Presence of withdrawal bleeding ecludes anatomic defects and chronic anovulation without estrogen.
Reproductive Pharmacology
Antiprogestins (mifepristone, ulipristal)
MOA: Competitive inhibitors of progestins at progesterone receptors.
Use: Termination of pregnancy (mifespristone with misoprostol); emergency contraception (ulipristal).
Reproductive Pharmacology
Combined contraception
Progestins and ethinyl estradiol.
MOA: Estrogen and progestins inhibit LH/FSH and thus prevent estrogen surge. No estrogen surge → no LH surge → no ovulation. Progestins cause thickening of cervical mucus and inhibit endometrial proliferation, limiting access of sperm to uterus and making endometrium less suitable for implantation.
Contraindications: smokers >35 (↑ risk of cardiovascular events), patients with ↑ risk of cardiovascular disease, migraine (especially with aura), breast cancer.
Reproductive Pharmacology
Copper intrauterine device
MOA: Produces local inflammatory reaction toxic to sperm and ova, preventing fertilization and implantation; hormone free.
Use: Long-acting reversible contraception. Most effective emergency contraception.
Adverse Effects: Heavier or longer menses, dysmenorrhea. Risk fo PID with insertion.
Reproductive Pharmacology
Terbutaline, ritodrine
MOA: β2-agonists that relax the uterus
Use: ↓ contraction frequency in women in labor
Reproductive Pharmacology
Danazol
MOA: Synthetic androgen that acts as partial agonist at androgen receptor.
Use: Endometriosis, hereditary angioedema
Adverse Effects: Weight gain, edema, acne, hirsutism, masculinzation, ↓ HDL levels, hepatotoxicity
Reproductive Pharmacology
Testosterone, methyltestosterone
MOA: Agonists at androgen receptors
Use: Treat hypogonadism and promote development of 2° sex characteristics; stimulate anabolism to promote recovery after burn or injury
Adverse Effects: Causes masculinization in females; ↓ intratesticular testosterone inn males by inhibiting release of LH (via negative feedback) → gonadal atrophy. Premature closure of epiphyseal plates. ↑ LDL, ↓ HDL
Reproductive Pharmacology
Finasteride
MOA: 5α-reductase inhibitor (↓ conversion of testosterone to DHT)
Use: BPH and male-pattern baldness
Reproductive Pharmacology
Flutamide
MOA: Nonsteroidal competitive inhibitor at androgen receptors
Use: Prostate carcinoma
