Chapter 34 Women's health drugs Flashcards
The development of the primary sex structures in the female reproductive system, initiation of reproductive functions (starting at puberty), and maintenance are controlled by?
pituitary gonadotropin hormones and the female sex steroid hormones—estrogens and progesterone.
Pituitary gonadotropins include?
follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which play a primary role in hormonal communication between the pituitary gland and the ovaries in the continuous regulation of the menstrual cycle from month to month.
Estrogens are also responsible for stimulating the development of?
secondary female sex characteristics and distribution of body fat and hair, creating optimal conditions for pregnancy in the endometrium just after ovulation, and promoting the start of menses.
The ovaries function both as endocrine glands and as reproductive glands. As reproductive glands, they?
produce mature ova within ovarian follicles, which are then ovulated or released into the space in the peritoneal cavity between the ovary and the fallopian tube.
Three major estrogens are synthesized in the ovaries: (1) estradiol (the principal estrogen), (2) esterone, and (3) estriol. Exogenous estrogens can be classified into two main groups:
(1) steroidal estrogens (e.g., conjugated estrogens, esterified estrogens, and estradiol)
(2) nonsteroidal estrogens (e.g., chlorotrianisene, dienestrol, and diethylstilbestrol [DES]).
Estradiol is the principal secretory product of the ovary and has several estrogenic effects. One of these effects is the regulation of gonadotropin (FSH and LH) secretion via negative feedback to the pituitary gland. Others include promotion of the development of women’s?
secondary sex characteristics, monthly endometrial growth, thickening of the vaginal mucosa, thinning of the cervical mucus, and growth of the ductal system of the breasts.
Progesterone is the principal secretory product of the corpus luteum and has progestational effects. This is required for?
endometrial egg implantation and maintenance of pregnancy.
Exogenous estrogenic drugs were developed because endogenous estrogens are inactive when taken orally. Synthetic drugs fall into two categories:
(1) steroidal and (2) nonsteroidal
Premarin is an estrogen mixture composed of?
conjugated estrogens, natural estrogen compounds equivalent to the average estrogen composition of the urine of pregnant mares.
-A nonanimal source is also available; Cenestin is conjugated estrogens from soy and yams.
Estrogens are used in the treatment or prevention of a variety of disorders that result primarily from?
estrogen deficiency. HRT to counter such estrogen deficiency is known for its benefits in treating menopausal symptoms.
Estrogens MOA
Binding of estrogen to intracellular estrogen receptors stimulates the synthesis of nucleic acids (DNA) and ribonucleic acids (RNA) and proteins
-estrogens required at puberty for development and maintenance of female reproductive system and development of female secondary sex characteristics (feminization)
Estrogens produce their effects in?
Estrogen-responsive tissues, which have a large number of estrogen receptors.
- These tissues include: female genital organs, breasts, pituitary gland, hypothalamus
- at time of puberty, production of estrogen increases greatly. This causes initiation of the menses, breast development, redistribution of body fat, softening of the skin, and other feminizing changes
Estrogens indications
Treatment or prevention of disorders that result from estrogen deficiency
- Atrophic vaginitis
- Hypogonadism
- Oral contraception (given with a progestin)
- Uterine bleeding
- Vasomotor spasms of menopause (“hot flashes”)
- Osteoporosis (treatment and prophylaxis)
- Breast or prostate cancer (palliative treatment)
- Ovarian failure or castration (or removal of ovaries)
Estrogens contraindications
Drug allergy Any estrogen-dependent cancer Undiagnosed abnormal vaginal bleeding Pregnancy Active thromboembolic disorder or history
Hormone replacement therapy (HRT) is used to?
Counter such estrogen deficiency and is most commonly known for its benefits in treating menopausal symptoms (hot flashes)
Estrogen contraindications
Drug allergy Any estrogen-dependent cancer Undiagnosed abnormal vaginal bleeding Pregnancy Active thromboembolic disorder or history (stroke or thrombophlebitis)
Estrogen adverse effects
- THROMBOEMBOLIC events: most serious
- Nausea: most common
- Hypertension, thrombophlebitis, edema
- Vomiting, diarrhea, constipation, abdominal pain
- May cause PHOTOSENSITIVITY, CHLOASMA (dermatologic effect)
- Amenorrhea, breakthrough uterine bleeding
- Tender breasts, fluid retention, headaches
Estrogen interactions
- Decrease the activity of the oral anticoagulants
- Decrease effect of rifampin
- St. John’s wort
- Tricyclic antidepressants
- Smoking
- Indicated for the treatment of many clinical conditions, primarily those resulting from estrogen deficiency
- Smallest dosage of estrogen that relieves the symptoms or prevents the condition is used
Estrogen therapy alone is associated with increased risk of ?
endometrial hyperplasia, a possible precursor of endometrial cancer. Adding progestin reduces the incidence.
Progestins include both natural and synthetic drugs. Progesterone is the most active natural progestational hormone; it is produced by the?
corpus luteum after each ovulation and during pregnancy by the placenta.
Progestins have a variety of uses, including treatment of?
Fibroids, uterine bleeding, primary and secondary amenorrhea and adjunctive and palliative treatment of some cancers and endometriosis
- can be used alone or in combination w/estrogens in prevention of conception
- preventing theatening miscarriage and alleviating symptoms of premenstrual syndrome
All progestin products produce the same physiologic
responses as those produced by progesterone itself, including?
induction of secretory changes in the endometrium, diminished endometrial tissue proliferation; increase in basal body temp.; thickening of vaginal mucosa; relaxation of uterine smooth muscle; stimulation of mammary alveolar tissue growth; feedback inhibition of the release of pituitary gonodotropins (FSH, LH); alterations in menstrual blood flow (especially in presence of estrogen)
Progestin: Megestrol (Megace) is commonly used as?
Adjunct therapy in Tx of breast and endometrial cancers
When estrogen replacement therapy is initiated after menopause?
Progestins are often included to decrease endometrial proliferation that can be caused by unopposed estrogen in women with an intact uterus
Formulations of progesteron itself are also used to treat?
Female infertility
The most serious undesirable effects of progestin use include?
liver dysfunction, thrombophlebitis, and thromboembolic
disorders such as pulmonary embolism.
Progestin interactions
Progestins may increase the effects of benzodiazepines and voriconazole
-Barbiturates, carbamazepine, phenytoin, rifampin, and St. John’s wort, which are all enzyme inducers, may DECREASE effectiveness of progestin
Decreased glucose tolerance may occur when progestins are taken with?
antidiabetic drugs
Progestin drug: Medroxyprogesterone (Depo-Provera)
- Inhibits secretionof pituitary gonadotropins, preventing follicular maturation and ovulation, stimulates growth of mammary tissue, has antineoplastic action against endometrial cancer
- used to Tx uterine bleeding, secondary amenorrhea, endometrial cancer, renal cancer, used as contraceptive
- used as adjunct therapy in certain cancers
- oral and parenteral preparations, long acting injection for mulation called Depo-Provera
- Depo-Provera used for birth control, one shot protects women for 3 months. Concern about use in women younger than 25 and use for longer than 2 years due to potential for bone density loss
Progestin drug: Megestrol (Megace)
- used in palliative management of recurrent, inoperable, or metastatic endometrial or breast cancer
- can cause appetite stimulation and weight gain, so used in management of anorexia, cachexia, unexplained substantial weight loss in pt’s with AIDS and cancer
- ORAL only
Contraceptives MOA
Prevent ovulation by inhibiting the release of gonadotropins and increasing uterine mucus viscosity, resulting in: Decreased sperm movement and fertilization of the ovum. Possible inhibition of implantation of a fertilized egg (zygote)
Oral contraceptives are the most effective form of birth
control currently available. Estrogen-progestin combinations contain both?
estrogenic and progestational steroids
The currently available oral contraceptives may be ?
biphasic, triphasic, or monophasic, in terms of the doses taken at different times of the menstrual cycle.
The biphasic drugs contain a fixed estrogen dose combined with a low progestin dose for the?
first 10 days and a higher dose for the rest of the cycle and are available in 21- or 28-day dosage packages.
The triphasic oral contraceptives contain three different
estrogen-progestin dose ratios that are administered sequentially during the cycle and are provided in?
21- or 28-day dosage packages. The triphasic products most closely duplicate the normal hormonal levels of the female cycle.
Contraceptives also come in monophasic forms, in which the estrogen and progestin doses are the?
same throughout the cycle. There are also oral contraceptives that are progestin-only drugs.
The monophasic and triphasic oral contraceptives are?
most numerous on the market and the most widely
prescribed.
Three other contraceptives are a long-acting injectable form of medroxyprogesterone, a transdermal contraceptive patch, and, most recently, an?
intravaginal contraceptive ring.
Contraceptive drugs prevent ovulation by inhibiting the
release of?
gonadotropins and by increasing uterine mucous viscosity, which results in:
(1) decreased sperm movement and fertilization of the ovum
(2) possible inhibition of implantation (nidation) of a fertilized egg (zygote) into the endometrial lining.
The contraceptive effect results mainly from the?
suppression of the hypothalamic-pituitary system, which in turn prevents ovulation
- Improve menstual cycle regularity
- decrease blood loss during menstruation
- decreased incidence of functional ovarian cysts and ectopic pregnancies
Oral contraceptives indications
-Primarily used to prevent pregnancy
-Other uses
Treatment of endometriosis and hypermenorrhea
Production of cyclic withdrawal bleeding
Postcoital emergency contraception
Oral contraceptives contraindications
-known drug allergy to a specific product, pregnancy, and
known high risk for or history of thromboembolic events (MI, venous thrombosis, pulmonary embolism, stroke)
Oral contraceptives adverse effects
Drawbacks to the use of these drugs include:
-Hypertension
-Thromboembolism, possible PE, myocardial infarction (MI), stroke
-Alterations in lipid and carbohydrate metabolism
-Increases in serum hormone concentrations
-These effects are caused by the estrogen component.
May also cause:
-Edema, dizziness, headache, depression, nausea, vomiting, diarrhea, increased appetite, increased weight, breast changes, many others
Oral contraceptives interactions
Drugs that decrease effectiveness of oral contraceptive drugs
-Antibiotics (especially penicillin and cephalosporin)
-Barbiturates
-Isoniazid
-Rifampin
Drugs that may have reduced effectiveness if given with oral contraceptives
-Beta blockers, warfarin, tricyclic antidepressants, vitamins, hypnotics, anticonvulsants, theophylline, and antidiabetic drugs
Nursing implication contraceptives
- Assess baseline vital signs, weight, blood glucose levels, and renal and liver function study results.
- Assess whether the patient smokes.
- Assess history and medication history.
- Assess contraindications, including potential pregnancy.
- For bisphosphonates, ensure that patients have no esophageal abnormalities and can remain upright or in a sitting position for 30 minutes after the dose.
- Estrogens and progestins
- Take the smallest dose needed.
- Give intramuscular doses deep in large muscle masses, and rotate sites.
- Give oral doses with meals to reduce GI problems.
- Teach patients about correct self-administration and what to do if a dose is missed.
Nursing implications for Estrogens and progestins:
- Increased susceptibility to sunburn may occur; advise patients to wear sunscreen or avoid sunlight.
- Instruct patients to report weight gain.
- Advise patients to complete annual follow-up examinations, including Pap smears and breast examinations.
- Follow specific administration guidelines carefully for administration of uterine relaxants or stimulants.
- Monitor the patient’s vital signs and fetal condition during therapy.
A woman has not taken her oral contraceptive since Monday. It is now Wednesday morning. What should she do now to prevent pregnancy?
Take the two missing doses as soon as possible.
Continue the drug as if no doses were missed.
Start over with a new monthly pack of oral contraceptives.
Resume the drug but also use a second form of birth control.
Resume the drug but also use a second form of birth control.
Rationale: Missed doses will reduce the effectiveness of the oral contraceptive, so another form of pregnancy prevention will be needed.
Obtain information on the patient’s past medical problems, history of menses and problems with the menstrual cycle, medications taken (prescribed and over-the-counter drugs and supplements), number of pregnancies and miscarriages, last menstrual period, and any?
related surgical or medical treatments.
Before initiating therapy with any of the hormonal drugs or other women’s health-related drugs, obtain the patient’s?
blood pressure and weight and document the findings.
Estrogen-only hormones are given after the following disorders and conditions have been ruled out:
any estrogen-dependent cancer, undiagnosed abnormal vaginal bleeding, active thromboembolic disorders such as stroke or thrombophlebitis, or a history of these
Important to assess for potential drug interactions such as with tricyclic antidepressants, which may reach toxic levels if given with?
Estrogens
Hormonal replacement is not recommended for women with histories of ?
endometrial cancer; in women with breast cancer, estrogen therapy has not been proven safe and may raise risk.
-bone density may also be impacted
With oral contraceptive drugs, perform a?
pregnancy test and assess for history of vascular and/or thromboembolic disorders.
Additionally, with progestins, assess for a history of?
liver/gallbladder disease, thrombophlebitis, and thromboembolic disorders due to possible adverse effects.
Raloxifene also decreases the effects of?
warfarin
Avoid smoking because of the risk for?
Thombosis
-smoking decreases effectiveness of estrogen
Estrogen interactions
- smoking
- oral anticoagulants (decreased effectiveness)
- rifampin
- Sto. John’s wort (decreased estrogen effectivenss)
Drugs that may have their therapeutic effects decreased if taken concurrently with oral contraceptives include?
Antiepileptic drugs, beta blockers, hypnotics, antidiabetic drugs, warfarin, theophylline, tricyclic antidepressants, vitamins
A significant drug interaction occurs with the antidiabetic drug and?
Progestins
Estrogen: If estradiol is being given, what is the indication?
Symptoms of menopause & it is given at the same time every day
If the estradiol transdermal patch is given, it is applied to?
One patch once or twice weekly to loser abdomen and not to breast or chest
Use of progestins is indicated for?
Birth control, such as the use of Depo-Provera with one IM injection every 3 months
-give in deep muscle mass, rotate sites
Depo-Provera is controversial in women of any reproductive age because?
Its associated bone density loss
Megestrol, a synthetic progestin, if often indicted for?
Palliative reasons or for management of anorexia, cachexia, or weight loss unexplained in AIDS
-given orally and to maximize appetite
Progestin-only oral contraceptive pills are taken?
daily at same time
- these pills lead to higher incidence of ovulatory cycles, so there is an increased rate and risk for contraceptive failure if not taken as instructed
- often for women older than 35 and breastfeeding
Combination estrogen-progestin pills contain?
Low doses of hormones
Biphasic oral contraceptives contain?
Fixed estrogen and variable progestin for 21-28 days
The low dose monophasic (fixed estrogen-progestin combination) types are provided as?
21-28 day of pills
Triphasic oral contraceptives offer?
3-4 of variable estrogen & progestin combinations
The reduction in the level of estrogen has been associated with a?
Decrease in adverse effects and a decrease in risk for complications; however more breakthrough bleeding may occur
