Pharmacology of Estrogens and Progestins Flashcards
What’s the main difference between tamoxifene and raloxifene?
Tamoxifene can cause endometrial and breast cancers, while raloxifene cannot.
What metabolic effects does estrogen have on the liver?
Decreased LDL and increased HDL (cardioprotective)
What is MHT?
Menopausal Hormone Therapy
Risk of ____________ in women being treated with MHT decreases with supplemental progestin.
endometrial cancer
What’s the difference between pharmacologic and physiologic doses of estrogen and progesterone?
Pharmacologic doses are much higher and are used to suppress gonadal hormones. Physiologic doses supplement absent estrogen and act to support end organs.
Rising ____________ during the follicular stage stimulates a positive feedback mechanism that increases secretion of ____________.
estradiol; LH
The __________ surge triggers ovulation.
gonadotropin
How are gonadotropins suppressed during the luteal phase?
Progesterone –stimulated by hCG on the corpus luteum –suppresses LH and FSH.
How do androgen antagonists affect the estrogen response element?
They also cause a conformational change, but they do so in a different way than estrogen, thus preventing transcription.
How does estrogen lead to thrombosis?
It stimulates the production of factors II, VII, IX, and X (just like how it up-regulates thyroid-binding globulin).
There is a reduced _____________ effect if estrogen is given transdermally.
hepatic
Estrogen is often used to treat __________________ in post-menopausal women.
vasomotor symptoms (e.g., hot flashes)
How can the risk of endometrial cancer be reduced in a patient taking estrogen?
They can switch to progestin for a brief bit each month.
Where do SERMs have agonist and antagonist activity?
Agonist in bone and liver (excellent!–mostly, there is also a rise in thromboembolic risk, however) and antagonist at breast and uterus (also excellent!).
Estrogen has _______________ bioavailability.
good
What other GI/metabolic disorder can estrogens cause?
Cholestatic jaundice
Use of hormonal contraceptives is contraindicated in ___________.
women older than 35 who smoke
In young women, estrogens are often used to treat ______________.
dysmenorrhea
What side effect does levonorgestrel (Plan B) have?
Emesis
What drug-drug interaction is most common with oral contraceptives?
Hormonal contraceptives are hepatically metabolized, so co-administration of rifampin or phenytoin (just to use two examples) can reduce contraceptive effect.
What does SERM stand for?
Selective Estrogen Receptor Modulator
Which SERM raises the risk of endometrial cancer
Tamoxifen
How does mifepristone work and what is it used for?
It is a progesterone antagonist that causes the corpus luteum to rupture. It is used for terminating early pregnancies –in conjunction with prostaglandins to stimulate uterine contraction.
Other than letrozole, what is another aromatase inhibitor?
Exemestane
What does estrogen do to the bone?
It stimulates closure of the epiphyseal plate.
Other than by inhibiting osteoclast differentiation, how else does estrogen increase bone strength?
It stimulates the production of osteoprotegerin, which binds and captures RANK-L.
Although raloxifen is great because it doesn’t increase risk of endometrial or breast cancer, it lacks one of the main therapeutic benefits of estrogen: ______________.
it cannot treat hot flashes
How doe tamoxifen and raloxifen affect clotting factors?
They, like estrogen, increase the concentration of clotting factors so they also predispose women to DVTs.
What is the mechanistic utility of medroxyprogesterone?
It does not inhibit the pituitary, so it can help end-organ lack of estrogen without disrupting the normal cycle.
The most successful contraceptive method is _______________.
subdermal implants followed by IUDs
Oral contraceptives increase the risk of _____________ cancer.
cervical
The best progestin to add to a regimen aimed at treating acne is _______________.
desogestrel
