Pharmacology - Nursing Flashcards
In this article, we cover the reproductive system medications estrogens and progestin, as well as uterine stimulants and tocolytic agents.
The Nursing Pharmacology video series follows along with our Pharmacology Second Edition Flashcards, which are intended to help RN and PN nursing students study for nursing school exams, including the ATI, HESI, and NCLEX.
When you see this Cool Chicken, that indicates one of Cathy's silly mnemonics to help you remember. The Cool Chicken hints in these articles are just a taste of what's available across our Level Up RN Flashcards for nursing students!
Estrogens - conjugated estrogen, estradiol (Estrace)
Estrogens, which include conjugated estrogen and estradiol, are indicated for contraception, post-menopausal osteoporosis, dysmenorrhea (painful menstruation; used in a combination estrogen/progesterone), or for prostate cancer.
Estrogens - mode of action
These medications bind to estrogen receptors in the body, promoting growth and development of female sex organs and secondary sex characteristics in women.
Estrogens - side effects
The main side effects of estrogens include embolic effects (i.e., blood clots). A patient taking estrogen is at higher risk for DVT, PE, an MI (myocardial infarction, or “heart attack”), or a stroke. Other side effects include hypertension, weight gain, edema (swelling caused by excess fluid trapped in the body's tissues), and increased risk of certain types of cancer, for example, estrogen-dependent breast cancers.
Estrogens - contraindications
This medication is contraindicated in patients who smoke, have hypertension, or who are at increased risk for blood clotting (embolic events). As noted above, some breast cancers are estrogen-dependent — a patient with an estrogen-dependent cancer should not be treated with estrogen.
Progesterones - medroxyprogesterone (Depo-Provera), norethindrone
Progesterones, which include medroxyprogesterone and norethindrone, can be used for contraception, either alone or in combination with estrogen. They can also be used in the treatment of dysmenorrhea (painful menstruation).
Progesterones - mode of action
Progesterones inhibit gonadotropin production, preventing follicular maturation and ovulation.
Progesterones - side effects
The side effects of progesterone include an increased risk for embolic events or blood clots, just as with estrogen — patients taking progesterone are at increased risk for DVT, PE, MI, and stroke; menstrual changes; edema; and an increased risk of breast cancer.
The injectable medication medroxyprogesterone (Depo-Provera) comes with an increased risk for bone loss.
Progesterones - contraindications
Progesterone is contraindicated for any patient who is at increased risk for blood clots.
This medication carries a black box warning due to the risk of decreased bone mineral density in patients who use Depo-Provera or injectable medroxyprogesterone. Patients being administered this medication should be encouraged to increase their intake of calcium and vitamin D.
Oxytocic - oxytocin (Pitocin)
Oxytocin and dinoprostone are medications used in the induction and enhancement of labor. Oxytocin may also be used in the treatment of postpartum hemorrhage.
Oxytocin - mode of action
Oxytocin works by stimulating the uterus.
Oxytocin - side effects
Side effects can include painful contractions, uterine rupture, and water intoxication (a form of acute hyponatremia, that is, abnormally low sodium).
Oxytocin - nursing care
A patient on oxytocin should have their contractions closely monitored — contractions should be 60 – 90 seconds in duration and occur every 2 – 3 minutes. If contractions are happening more frequently or lasting longer, it may be necessary to discontinue oxytocin. It will also be important to monitor maternal and fetal blood pressure and pulse.
Note that magnesium sulfate may be used to help relax the uterus if hyper-stimulation of the uterus occurs due to oxytocin.
Uterine stimulant - methylergonovine (Methergine)
Methylergonovine is another uterine stimulant and is used for postpartum hemorrhage.
Methylergonovine - mode of action
Methylergonovine has the same mode of action as oxytocin, that is, it stimulates the uterus.
Methylergonovine - side effects
Side effects can include abdominal pain, nausea and vomiting, and hypertension.
Methylergonovine - contraindications
A patient who has hypertension should not receive this medication.
Tocolytic (preterm labor) - terbutaline (Bricanyl)
Terbutaline is a tocolytic agent used in the treatment of preterm labor. It helps to delay labor but will not prevent it.
When flying, turbulence delays arrival time (just like terbutaline delays arrival of the baby).
Terbutaline is also used for asthma and COPD.
Terbutaline - mode of action
The mode of action of terbutaline is to activate Beta-2 receptors, which helps to relax the uterus.
It also causes bronchodilation, which is why it's used to treat asthma and COPD.
Terbutaline - side effects
This medication has many side effects, including tachycardia, angina, hypokalemia (low blood levels of potassium), dysrhythmias (irregular beating of the heart), restlessness, and tremor.
Note that this medication comes with a black box warning due to the risk for significant maternal and fetal distress if it’s used for more than 48 hours.
Terbutaline - contraindications
Terbutaline is for short-term use only — under 48 hours (as noted above). Its use should be limited to pregnancies under 37 weeks in gestation.
Remember that there are other tocolytic agents that can be used for preterm labor, including magnesium sulfate, as well as nifedipine, which is a calcium channel blocker.