Pharmacology of sex hormones Flashcards
What are the most widely used form of hormonal contraception due to their ease of use and effectiveness
Oral contraceptives
What are the estrogen components of oral contraceptives, which is metaobolized to other
Ethyinyl estradiol and mestranol, mestranol is metabolized to ethinyl estradiol in liver and gut
What allows the estrogen components to be orally available in oral contraceptives
Ethinyl group (C triple bond C)
What are the first generation progestins
norethindrone, ethynodiol diacetate, norgestrel, norethindrone acetate
What is the 2nd generation progestin
Levonorgestrel
What are the 3rd generation progestin
Norgestimate and Desogestrol
What is the 4th generation progestin, what is interesting about this agent
Drospirenone, has no estrogenic or androgenic activity with low to no progestational activity
What is the biggest setback of first generation progestins
They have estrogenic activity causing side effects
Which progestin agents has the most progestational activity, which has the most androgenic activity, little to no estrogenic activity
Levonorgestrel and Desogestrel, Levonorgestrel has the most androgenic activity while Desogestrel has little to no estrogenic activity
What is the mechanism of action of combination oral contraceptives
Suppress LH and FSH causing no mid-cycle LH surge thus preventing ovulation
T/F: Having only a estrogen component or a progestin component alone prevents ovulation but a combination acts synergistically and consistently
True
What is the MOA of estrogens in oral contraceptives
Primary effect is stabilize endometrial lining and provide cycle control causing less bleeding, suppress FSH release, possibly block LH surge and ovulation
What is the MOA of progestins in oral contraceptives
Primary effect is it diminshes the frequency of GnRH pulses and blocks LH surge preventing ovulation, produces thick mucus
T/F: Estrogens provide the most contraceptive effect
False: Progestins provide the most contraceptive effect
What does it mean if an Oral contraceptive is combined monophasic
One concentration of etrogenic component and one concentration of progestin component
T/F: If an oral contraceptive is triphasic that means it has diffferent concentrations of components scheduled for different days
True
What are risk in taking oral contraceptives
Cardiovascular, increased risk of venous thromboembolism, acute heart attack in smokers with hypertension over the age of 35
What is perimenopause, how long is it
Period preceding to menopause, 2-8 years
What are symptoms of perimenopause/menopause
Vasomotor symptoms, Hot flashes, night sweats, irregular bleeding, vaginal dryness
What is hormone replacement therapy
Medications containing female hormones to replace the ones the body no longer makes after menopause
Why would estrogen-based hormone replacement therapy be used
Primarily used for treatment of vasomotor and urogenital symptoms of menopause and for prevention of osteoporosis
When would progestin be added hormone replacement therapy, when would a patient only take estrogen-based HRT
Endometrail hyperplasia and carcinoma, Hypersectomy
What is the biggest risk for using hormone replacement therapy
Endometrial (uterine) cancer, venous thromboembolism, breast cancer, gallbladder disease
What are the two most common Selective estrogen receptor modulators (SERMs), what is their MOA
Tamoxifen and Raloxifene, bind to estrogen receptors but cause their conformation to no longer support cancer growth
Why are aromatase inhibitors used
Prevent testosterone from being converted to estrogen thus preventing more tumor growth in breast cancer
What is an irreversible aromatase inhibitor, what is a reversible aromatase inhibitor
Exemestane/ Anastrozole and Letrozole
T/F: Reversible aromatse inhibitors can also be used in female infertility and gynecomastia in children and adolescents
True
What is the MOA of antiandrogens
inhibit circulating androgens by blocking androgen receptors and/or suppressing androgen synthesis, inhibits gonadotropin secretion reducing LH and FSH and testosterone
What is the most common antiandrogens, when would it be used, side effects
Cyproterone acetate/ prostate cancer/ feminization, reversible infertility sexual dysfucntion, fatigue, irritability
When are gonadotropins given to patients, what are they, who are they purified from
Treat infertility in patients with gonadotropin deficiency, Human menopausal gonadotropin (hMG): urine of postemopausal women, Human chorionic goadotropin (hCG): from urine of pregnant women
T/F: hMG has mostly LH while hCG has a mixture of FSH and LH
False: Human menopausal gonadotropin has a mixture of FSH and LH while Human chorionic gonadotropin is mostly LH
How do GnRH (LHRH) lead to less LH and FSH, what is a risk of this therapy
Initially promote LH and FSH but after longer exposure (10 days) the receptors undergo desensitization and internalize causing a decrease in FSH and LH, tumor growth due to increase testosterone and Estrogens
What is a typical GnRH agonist
Goserelin
What is MOA GnRH antagonists
Competitively and reversibly bind to GnRH receptor thereby LH and FSH relase from the pituitary
