Pharm Chapter 34: Women's Health Drugs

During a postpartum patient assessment, the nurse notes a boggy uterus and increased vaginal bleeding. Based on this assessment data, the nurse prepares to administer which medication? a. Oxytocin (Pitocin) b. Clomiphene (Clomid) c. Terbutaline (Brethine) d. Dinoprostone (Prostin E2)

a. Oxytocin (Pitocin) Oxytocin is a uterine stimulant that causes uterine contractions, which would decrease the vaginal bleeding.

What is the most common drug used for induction of labor in pregnant women and to promote ejection of milk during lactation? a. Oxytocin (Pitocin) b. Clomiphene (Clomid) c. Misoprostol (Cytotec) d. Mifepristone (Mifeprex)

a. Oxytocin (Pitocin) Oxytocin is a naturally occurring hormone that can be given in synthetic form for induction of labor.

Which laboratory test would the nurse expect the health care provider to prescribe to monitor a patient for adverse effects related to progestin medications? a. Cardiac enzymes b. Liver function tests c. Complete blood count d. Serum creatinine level

b. Liver function tests One of the most serious undesirable adverse effects of progestins is liver dysfunction, which would be assessed by monitoring liver enzymes.

When educating a patient about the use of oral contraceptives, the nurse provides what explanation for the pills having different colors each week? a. "They help you remember which week you are taking." b. "There isn't a reason for the color; it's just the choice of the drug company." c. "The different color pills are because of different amounts of hormones in each week." d. "They are color coded for the weeks of the month."

c. "The different color pills are because of different amounts of hormones in each week." Oral contraceptive pills can be monophasic, biphasic, or triphasic. If the pills are different colors, they have different amounts of hormones and are likely the triphasic type of contraceptive.

An elderly female patient being treated for osteoporosis with a selective estrogen receptor modulator (SERM) should alert the nurse for an increased risk of which condition? a. Hypertension b. Hypercalcemia c. Deep vein thrombosis d. Coronary heart disease

c. Deep vein thrombosis The use of SERMs is contraindicated in postmenopausal women with venous thromboembolic disorders, such as deep vein thrombosis.

A female patient arrives to the clinic for counseling on potential hormone replacement therapy. When taking the patient's history, which condition would the nurse consider as a contraindication to use of hormone replacement therapy for the patient? a. Osteoporosis b. Hyperlipidemia c. Thromboembolic events d. Early onset of menarche

c. Thromboembolic events A contraindication for estrogen administration is any history of thromboembolic disorder.

Which statement by the patient indicates an understanding of discharge teaching for the medication alendronate (Fosamax)? a. "I need to decrease my intake of dairy products to prevent hypercalcemia." b. "This medication will help relieve the bone pain I have from my osteoporosis." c. "I need to take this medication with food to prevent damage to my esophagus caused by reflux of stomach acid." d. "I will take the medication in the morning before I eat with 8 oz of water and remain upright for 30 minutes."

d. "I will take the medication in the morning before I eat with 8 oz of water and remain upright for 30 minutes." Alendronate can cause erosive esophagitis. To prevent this adverse effect, it is important for the patient to take the medication with an 8-oz glass of water in the morning on an empty stomach without any other medications and maintain an upright position for 30 minutes. These actions facilitate rapid absorption and prevent reflux into the esophagus.

The nurse would question a prescription for estrogen replacement therapy in a patient with a history of which condition? a. Weight loss b. Dysmenorrhea c. Vaginal bleeding d. Deep vein thrombosis

d. Deep vein thrombosis Increased coagulation and risk of deep vein thrombosis are serious adverse effects of hormone replacement therapy.

Drugs for Osteoporosis

-Approximately 8 million women in the United States are currently affected by osteoporosis. -Supplementation with calcium and vitamin D are thought to play a role in the prevention of this common bone disorder. -Several drug classes are used for the treatment of existing osteoporosis: the bisphosphonates, the selective estrogen receptor modulators (SERMs), the hormones calcitonin and teriparatide, and most recently, denosumab. • The bisphosphonates work by inhibiting osteoclast- mediated bone resorption, which in turn indirectly enhances bone mineral density. • Raloxifene helps prevent osteoporosis by stimulating estrogen receptors on bone and increasing bone density in a manner similar to that of the estrogens themselves. • Like the natural thyroid hormone, calcitonin directly inhibits osteoclastic bone resorption. • Teriparatide is the first and currently the only drug available that acts by stimulating bone formation; it is a derivative of parathyroid hormone. • Denosumab (Prolia) is a monoclonal antibody that blocks osteoclast activation, thereby preventing bone resorption. • The primary adverse effects of SERMs are hot ashes and leg cramps. SERMs can increase the risk of venous thromboembolism, are teratogenic, and may result in leukopenia. • The most common adverse effects of bisphosphonates are headache, gastrointestinal (GI) upset, and joint pain. There is a risk of esophageal burns if they become lodged in the esophagus before reaching the stomach. The patient must take these medications with a full glass of water and remain sitting upright or standing for at least 30 minutes afterward. • Common adverse effects of calcitonin include ushing of the face, nausea, diarrhea, and reduced appetite. • Common adverse effects of teriparatide include chest pain, dizziness, hypercalcemia, nausea, and arthralgia. Infections occur with higher incidence in those taking denosumab.

Estrogens

-Exogenous estrogenic drugs were developed because endogenous estrogens are inactive when taken orally. Synthetic drugs fall into two categories: (1) steroidal and (2) nonsteroidal. Nonsteroidal estrogen products are no longer available in the United States because major adverse effects occurred when DES was used in obstetrics. -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. -Estrasorb is a new form of estrogen therapy that is a soy- based emulsion applied like a lotion. Other studies have found that soy reduces both low-density lipoprotein and total cholesterol levels. -Two new estrogen-related products that have been recently approved include duavee (conjugated estrogen/bazedoxifene) and osphena (ospemifene). Duavee is indicated for hot ashes associated with menopause and osteoporosis. Ospemifene (Osphena) is an estrogen agonist/antagonist that is the rst drug approved to treat moderate to severe dyspareunia (painful intercourse) in postmenopausal women. -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. -Contraindications for estrogen administration include known drug allergy, any estrogen-dependent cancer, undiagnosed abnormal vaginal bleeding, pregnancy, and active thromboembolic disorder. -The most serious adverse effects are thromboembolic events. -Estrogens can have an impact on the activity or toxicity of the oral anticoagulants, rifampin and St. John's wort, and tricyclic antidepressants. -Smoking should be avoided during estrogen therapy, because this can diminish the estrogenic effect and add to the risk for thrombosis. -Estrogen therapy alone is associated with increased risk of endometrial hyperplasia, a possible precursor of endometrial cancer. Adding progestin reduces the incidence.

Fertility Drugs

-Infertility in women is often the result of absence of ovulation (anovulation), which is normally due to various imbalances in female reproductive hormones. • Exogenous administration of estrogens or progestins may be used to fortify the blood levels of these hormones when ovarian output is inadequate. • Hormone deficiencies at the hypothalamic and pituitary levels are often treated with gonadotropin ovarian stimulants. • Representative examples of ovulation stimulants include the drugs clomiphene, menotropins, and choriogonadotropin alfa. • Clomiphene is a nonsteroidal ovulation stimulant that works by blocking estrogen receptors in the uterus and brain, resulting in a false signal of low estrogen levels to the brain. This leads to ovulation and increases the likelihood of conception in a previously infertile woman. • Menotropins is the drug name for a mixture of FSH and LH that is derived from the urine of postmenopausal women. These drugs are used primarily for the promotion of ovulation in anovulatory female patients. They may also be used to promote spermatogenesis in infertile men. • Few drugs interact with fertility drugs. The most notable are the tricyclic antidepressants, the butyrophenones, the phenothiazines, and the antihypertensive drug methyldopa.

Uterine Stimulants

-Medications are used to alter the dynamics of uterine contractions either to promote or to prevent the start or progression of labor. In the postpartal period, medications may be used to promote rapid shrinkage of the uterus to reduce the risk of postpartum hemorrhage. • Four types of drugs are used to stimulate uterine contractions: (1) ergot derivatives, (2) prostaglandins, (3) the progesterone antagonist mifepristone (RU-486), and (4) the hormone oxytocin. These collectively called oxytocics, as they mimic the natural hormone oxytocin. • Oxytocin is one of the two hormones secreted by the posterior lobe of the pituitary gland. • During childbirth, oxytocin stimulates uterine contraction, and during lactation it promotes the movement of milk from the mammary glands to the nipples. • Another class of oxytocic drugs is the prostaglandins, natural hormones involved in regulating the network of smooth muscle fibers of the uterus. • Oxytocin is available in a synthetic injectable form (e.g., Pitocin). This drug is used to induce labor at or near full- term gestation and to enhance labor when uterine contractions are weak and ineffective. Oxytocin is also used to prevent or control uterine bleeding after delivery, to induce completion of an incomplete abortion, and to promote milk ejection during lactation. • Ergot alkaloids are used after delivery of the infant and placenta to prevent postpartum uterine atony (lack of muscle tone) and hemorrhage. • Mifepristone is used to induce abortion and is often given with the synthetic prostaglandin drug misoprostol for this purpose.

Contraceptive Drugs

-Oral contraceptives are the most effective form of birth control currently available. Estrogen-progestin combinations contain both estrogenic and progestational steroids. • Oral contraceptives containing a combination of estrogens and progestins are the most effective forms of reversible contraception currently available. • 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 newest are the extended-cycle oral contraceptives. • 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 the 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 and (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. • Oral contraceptive drugs are primarily used to prevent pregnancy. In addition, they are used to treat endometriosis and hypermenorrhea, produce cyclic withdrawal bleeding in patients with amenorrhea, and occasionally to provide post-coital emergency contraception. • Contraindications to the use of oral contraceptives include known drug allergy to a specific product, pregnancy, and known high risk for or history of thromboembolic events. • Common adverse effects include hypertension, thromboem-bolism, alterations in carbohydrate and lipid metabolism, increases in serum hormone concentrations, and alterations in serum metal and plasma protein levels.

Drugs for Preterm Labor Management

-Preterm labor is de ned as substantial uterine contractions that could progress to delivery and occur before the 37th week of pregnancy. • Drugs given to inhibit labor and maintain the pregnancy are called tocolytics. They work by relaxing uterine smooth muscle. • Management of preterm labor includes the use of the nonsteroidal anti-inflammatory agent, indomethacin (the most effective tocolytic), and the calcium channel blocker, nifedipine.

Progestins

-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 uterine bleeding and amenorrhea and adjunctive and palliative treatment of some cancers. -All progestin products produce the same physiologic responses as those produced by progesterone itself, including induction of secretory changes in the endometrium. -Progestins are useful in the treatment of functional uterine bleeding caused by a hormonal imbalance, fibroids, or uterine cancer; in the treatment of primary and secondary amenorrhea; in the adjunctive and palliative treatment of some cancers and endometriosis; and, alone or in combination with estrogens, in the prevention of conception. -The most serious undesirable effects of progestin use include liver dysfunction, thrombophlebitis, and thromboembolic disorders such as pulmonary embolism. -Decreased glucose tolerance may occur when progestins are taken with antidiabetic drugs.

Anatomy, Physiology, and Pathophysiology Overview

-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) and (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.

A patient taking oral contraceptives is being treated for a urinary tract infection with antibiotics. Which information should the nurse include as education related to the oral contraceptives? a. "Report any abdominal pain, blood in the urine, or changes in vision." b. "There is no drug interaction between oral contraceptives and antibiotics." c. "Use an alternative method of birth control for up to 1 month during and after antibiotic use." d. "Your sexual partner should use a nonprescription test kit that will detect a urinary tract infection."

c. "Use an alternative method of birth control for up to 1 month during and after antibiotic use." When a patient takes oral contraceptives and is prescribed an antibiotic, the oral contraceptive effectiveness can be decreased, and an alternative method of birth control should be used for at least 1 month during and after taking certain antibiotics.

The combined continuous administration of progestin and estrogen reduces the risk of which cancer? a. Breast b. Vaginal c. Ovarian d. Endometrial

d. Endometrial Estrogen, given alone, has been associated with an increased risk of endometrial hyperplasia, which can lead to endometrial cancer. Progestin reduces the incidence of endometrial hyperplasia.