ESTROGEN
Estrogens are a family of related molecules that stimulate the development and maintenance of female characteristics and sexual reproduction. The natural estrogens produced by women are steroid molecules, which means that they are derived from a particular type of molecular skeleton containing four rings of carbon atoms, giving the shape shown here. The most prevalent forms of human estrogen are estradiol and estrone. Both are produced and secreted by the ovaries, although estrone is also made in the adrenal glands and other organs.
Synthetic Estrogen can be administered by mouth, by injection, as a topical cream or by several other routes. It works by replacing estrogen that is normally produced by the body. Estrogen is used to treat hot flushes ('hot flashes'; sudden strong feelings of heat and sweating) in women who are experiencing menopause ('change of life', the end of monthly menstrual periods).
Some brands of estrogen are also used to treat vaginal dryness, itching, or burning, or to prevent osteoporosis (a condition in which the bones become thin and weak and break easily) in women who are experiencing or have experienced menopause. However, women who need a medication only to treat vaginal dryness or only to prevent osteoporosis should consider a different treatment. Some brands of estrogen are also to relieve symptoms of low estrogen in young women who do not produce enough estrogen naturally. Some brands of estrogen are also used to relieve the symptoms of certain types of breast and prostate (a male reproductive gland) cancer.
Paradoxically, estrogen can be both a beneficial and a harmful molecule. The main beneficial effects of estrogen include its roles in
- Programming the breast and uterus for sexual reproduction,
- Controlling cholesterol production in ways that limit the buildup of plaque in the coronary arteries, and
- Preserving bone strength by helping to maintain the proper balance between bone buildup and breakdown.
Unfortunately, in addition to these important beneficial effects, estrogen can also be harmful. The most serious problem arises from the ability of estrogen to promote the proliferation of cells in the breast and uterus. Although this ability to stimulate cell proliferation is one of estrogen's normal roles, it can also increase a woman's chance of developing breast or uterine cancer.
The Food and Drug Administration has recently issued a set of cautions regarding the use of Estrogen. These cautions are outlined in the table below:
WARNING
Estrogen increases the risk that you will develop endometrial cancer (cancer of the lining of the uterus [womb]). The longer you take estrogen, the greater the risk that you will develop endometrial cancer. If you have not had a hysterectomy (surgery to remove the uterus), you should be given another medication called a progestin to take with estrogen. This may decrease your risk of developing endometrial cancer, but may increase your risk of developing certain other health problems, including breast cancer. Before you begin taking estrogen, tell your doctor if you have or have ever had cancer and if you have unusual vaginal bleeding. Call your doctor immediately if you have abnormal or unusual vaginal bleeding during your treatment with estrogen. Your doctor will watch you closely to help ensure you do not develop endometrial cancer during or after your treatment.
In a large study, women who took estrogen with progestins had a higher risk of heart attacks, strokes, blood clots in the lungs or legs, breast cancer, and dementia (loss of ability to think, learn, and understand). Women who take estrogen alone may also have a higher risk of developing these conditions. Tell your doctor if you smoke or use tobacco, if you have had a heart attack or a stroke in the past year, and if you or anyone in your family has or has ever had blood clots or breast cancer. Also tell your doctor if you have or have ever had high blood pressure, high blood levels of cholesterol or fats, diabetes, heart disease, lupus (a condition in which the body attacks its own tissues causing damage and swelling), breast lumps, or an abnormal mammogram (x-ray of the breast used to find breast cancer).
The following symptoms can be signs of the serious health conditions listed above. Call your doctor immediately if you experience any of the following symptoms while you are taking estrogen: sudden, severe headache; sudden, severe vomiting; speech problems; dizziness or faintness; sudden complete or partial loss of vision; double vision; weakness or numbness of an arm or a leg; crushing chest pain or chest heaviness; coughing up blood; sudden shortness of breath; difficulty thinking clearly, remembering, or learning new things; breast lumps or other breast changes; discharge from nipples; or pain, tenderness, or redness in one leg.
You can take steps to decrease the risk that you will develop a serious health problem while you are taking estrogen. Do not take estrogen alone or with a progestin to prevent heart disease, heart attacks, strokes, or dementia. Take the lowest dose of estrogen that controls your symptoms and only take estrogen as long as needed. Talk to your doctor every 3-6 months to decide if you should take a lower dose of estrogen or should stop taking the medication.
You should examine your breasts every month and have a mammogram and a breast exam performed by a doctor every year to help detect breast cancer as early as possible. Your doctor will tell you how to properly examine your breasts and whether you should have these exams more often than once a year because of your personal or family medical history.
Tell your doctor if you are having surgery or will be on bed rest. Your doctor may tell you to stop taking estrogen 4-6 weeks before the surgery or bed rest to decrease the risk that you will develop blood clots.Talk to your doctor regularly about the risks and benefits of taking estrogen.
(Source: NIH - MedlinePlus Drug Information)
