Estrogens

by Food and Drug Administration (FDA)

How you take a drug makes a big difference in how well it will work and how safe it will be for you. Dose timing, what and when you eat, and many other factors can mean the difference between feeling better, staying the same, or even feeling worse. This drug information page is intended to help you make your treatment work as well as possible. It's important to note, however, that this is only a guideline. You should talk to your doctor or pharmacist about how to take any prescribed drug.

This installment in a series of articles on commonly prescribed drugs is about estrogens. The focus is on estrogen deficiency problems. For information about another major estrogen use, oral contraceptives, see "'The Pill' May Not Mix Well with Other Drugs" in the March 1987 FDA Consumer.

Estrogens are the hormones mainly responsible for female sex characteristics. They assist in preparing girls' bones for rapid growth in adolescence. In women, estrogens maintain tone and elasticity of the urinary and reproductive organs and protect against bone thinning.

Men also make the hormone, but only a small amount. In both men and women, estrogens help stabilize the opening and closing of blood vessels.

Women manufacture most estrogens in the ovaries and adrenal gland, with increases during pregnancy from the placenta. Men produce low levels of estrogens in the testes. Fat cells also may produce estrogens.

Therapeutic estrogens made synthetically or derived from pregnant mares' urine are formulated as oral, injectable and vaginal preparations and, most recently, as stick-on patches.

Uses for These Drugs

The most common treatment use for these drugs is estrogen replacement therapy to treat symptoms of menopause (including menopause surgically induced by removal of the ovaries) to prevent the sweating episodes called hot flashes and the shrinking and irritation that sometimes occur in the vulva, vagina, and urinary organs. Because of the effects estrogen deficiency can have on the vagina, some menopausal and postmenopausal women have pain during or after intercourse. Estrogen therapy helps relieve this symptom by thickening the vaginal wall. Medical evidence hasn't proven that estrogens keep a woman feeling young or foster soft or unwrinkled skin. There is no evidence that they ease emotional and nervous symptoms, except in association with other postmenopausal symptoms such as hot flashes.

Other deficiency conditions that can be treated by estrogen use include failure of the ovaries to develop and premature failure of the ovaries.

In addition to the above uses, the Food and Drug Administration has approved estrogens to treat the following conditions:

Abnormal uterine bleeding due to hormonal imbalance

Breast cancer in some men and women whose disease has spread to other organs.

Advanced prostate cancer

FDA has approved Premarin?the original brand of conjugated (blended) estrogens for use in menopausal and postmenopausal women to help prevent bone loss due to osteoporosis, a bone-thinning condition.

In June 1990, FDA's Fertility and Maternal Health Drugs Advisory Committee concluded that estrogen replacement therapy with Premarin may reduce a woman's risk of diseases of the heart and blood vessels. FDA is currently evaluating the committee's report.

The agency also is evaluating the situation with generic conjugated estrogens. In February 1990, FDA proposed withdrawing approval of these products' marketing applications. Though generic conjugated estrogens are similar to Premarin, they are not identical, and their differences may affect their safety and effectiveness. For example, they might be less effective or ineffective in preventing osteoporosis.

How to Take Estrogens

As with all drugs, patients should take estrogens exactly as directed and should never give their medication to someone else. They should use the lowest dose needed, for the shortest time possible, and only for the prescribed treatment.

Oral estrogens are given once daily, whereas patches are changed twice weekly. When the physician deems it desirable to simulate the menstrual cycle, doses continue for three weeks, followed by a week without treatment. Taking oral estrogens at the same time each day establishes a routine and provides the greatest benefit with the least chance of side effects.

If nausea is a problem, taking the tablet with food or immediately after a meal may help. This symptom usually disappears with continued use.

When using the estrogen stick-on patch:

• Read directions carefully.
• Wash and dry hands before and after handling.
• Apply patch to the abdomen on a clean, dry, non-oily, hairless area free of cuts and irritation.
• Press firmly about 10 seconds, particularly around the edges.
• To avoid irritation, apply each dose to a different area, allowing at least a week to pass before an area is used again.
• Reapply a loosened patch or discard it and apply a new patch.
• Never apply a patch to the breasts or to an area such as the waist where clothing might rub it loose.

Clinical data support only cyclic short-term use of vaginal estrogen cream. To apply:

• Puncture dispensing end of tube with plastic spike on cap.
• Screw nozzle end of applicator to end of tube.
• Squeeze cream into applicator barrel until it reaches prescribed dosage, usually full or half full
• Unscrew applicator from tube.
• Lie on back with knees drawn up and then gently insert applicator deeply into vagina and press plunger downward to its original position.

To clean the applicator, pull the plunger from the barrel and wash it with mild soap and warm water. Do not boil or use hot water.

Missed Doses

Take a missed tablet as soon as possible, but skip it if it's almost time for the next one; this applies to patches, too. Never double an oral dose, and wear only one patch at a time.

Relief of Symptoms

The body readily absorbs estrogens into the bloodstream through the skin, vagina or intestines. Thus, therapy usually begins relieving menopausal symptoms such as hot flashes within a day or two. These problems may recur during the week off the drug, but they usually don't reach pre-treatment intensity.

About the Author

www.fda.gov
FDA is A United States government body that oversees medical devices, including contact lenses, intraocular lenses, excimer lasers and eyedrops. In the US, these products must be approved by the FDA before they can be marketed.