OB-GYN and Genitourinary Drugs Flashcards
Short acting, non-permanent methods of birth control; 2 different types; take daily to suppress release LH and FSH by the pituitary glands so ovulation does not occur
First approved in the 60s and later became popular
Formulations have now changed to lower doses
Available in a variety of formulations
Most are given as 21 tablets of either a fixed dose or varying dose followed by a week of placebo or iron tablets (this “gap” is when the withdrawal bleed occurs)
Oral Contraceptives (OCs)
most popular type of OC; use both synthetic estrogen and a synthetic progestin in combination
COCPs–combined oral contraceptives
Synthetic progestin only; prevents ovulation if taken for more than one cycle;
Provides pregnancy protection by:
thickening cervical mucous and preventing the uterine lining from maturing enough to accept fertilized ovum
*less effective for pregnancy prevention but is better to use for women with risk of cancer and CV
the “mini-pill”
LH
Luteinizing hormone
FSH
Follicle stimulating hormone
They also:
- thicken cervical mucous, impeding sperm passage
- thin uterine lining–interferes with implantation of fertilized egg
- prevent shedding of endometrium, potentially preventing menstruation
- All OCs can act as abortifacients
Other effects of oral contraceptives
- some indication that OCs slightly increase risk of breast cancer
- increase risk of thromboembolic events (DVTs, PE and stroke)
contains a fixed dose of an estrogen and a progestin
Monophasic OC pill
have a fixed amount of estrogen with 2 different amounts of progestin
Biphasic OC pill
the amount of the progestin (usually) varies 3 times during the cycle
Triphasic OC pill
drugs are the same as OCs but are administered other ways: injection, vaginal rings, patches, subcutaneous implants and intrauterine devices
Non-Oral Contraceptives
A q3 week vaginal insert that slowly leaks a combo of estrogen and progestin
Vaginal Ring (NuvaRing)
Progestin-only drugs like Depo-Provera (medroxyprogesterone); sometimes used:
because of safety (history of DVT or pulmonary embolism)
because of convenience and flexibility of 4/year dosing
as a fail-safe method for irresponsible patients
Injection
The only one currently available marketed in the U.S.; shown to be effective as a COCP with perfect use
Ortho Evra Transdermal Patch
Consist of 1-2 small silicone rods implanted under the skin about ever 3 years; rods slowly leach a progesterone-only drug;
These devices have been very popular worldwide because of their ease of use, reliability and low rate of adverse effects
*newer ones last 4-5 years
Implantable contraceptives
the old standbys: condoms, diaphragms and cervical caps
Barrier methods of contraception
Temporary devices that disrupt implantation by virtue of their presence in the uterine cavity; most also store a progestin drug slowly released to prevent ovulation
IUD-Intrauterine Device
FDA approved COCP marketed to eliminate periods or reduce frequency
(90mcg levonorgestrel / 20mcg ethinyl estradiol
Lybrel
using the abortifacient properties of COCPs as a “morning after pill”; can reduce risk of pregnancy by as much as 89%
(i.e. the progestogen-only (levonorgestrel) pill “Plan B”, which makes the uterus inhospitable to implantation; better sooner than later because it won’t stop pregnancy once an ovum is implanted)
Emergency Contraception
Technically all COCPs are included but this really refers to a group of meds that terminate an established pregnancy (usually 1st tri); called ‘medical abortion’
*mifepristone (Mifeprex) or RU-486–an anti-progesterone drug that causes vigorous contractions of the uterus to terminate pregnancy
Abortifacients
The first OC approved for treating premenstrual dysphoric disorder (PMDD); Yasmin was its predecessor; became the most popular OC by 2008
Is formulated with a manmade hormone drospirenone, which mimics female progesterone
*approved for contraception and treatment of moderate acne and PMDD but has potentially serious side effects (shouldn’t be take by all)
Yaz
The most severe form of PMS (affects 5% of women); some believe they are separate disorders;
- symptoms are noticeable depressed mood with anger, irritability, anxiety, muscle and headaches
- SSRI antidepressants like Prozac are treatment
PMDD–Premenstrual dysphoric disorder
the practice of replacing declining levels of natural estrogens with conjugated estrogens from equine sources (Premarin)
- used to be the preferred drug therapy until the early 2000s to treat hot flashes, irritability, weight gain, insomnia, bone loss (preserves bone mass)
- Doubts about safety because of the 20-year Women’s Health Initiative
MHT–Menopausal hormone therapy
Large, 20-year study done on over 160k women from 21 countries (52k WITH breast cancer and 100k WITHOUT) because of suspicions about using MHT; study began in 1991;
1st data announce in 2002 led to big changes in medical practice–data showed that:
-women using HRT for 5+ years had 35% increased risk of breast cancer
-sales of Premarin for HRT dropped drastically
*risk remained during HRT use but went away 5 years after cessation
Women’s Health Initiative–WHT
*As a result: 3 other drug strategies developed to preserve bone mass and prevent osteoporosis complications:
Calcium supplements
Bisphosphonate drugs–qweekly drug alendronate (Fosamax)
SERMs–Estrogen receptor agonists (Evista)
