There are numerous hormone replacement therapy (HRT) drugs approved by the United States Food and Drug Association. These are usually used to treat hot flashes or vaginal changes or for the prevention of osteoporosis in women who are postmenopausal or who have had their ovaries removed. Hormone therapy in women who still have their uterus should include an estrogen and a progestin to minimize the risk of uterine cancer.
These come in various forms ranging from conjugated equine estrogens to synthetic estrogen compounds. Estradiol and estropipate are other forms. These drugs are usually administered once daily and come in doses of 0.3 milligrams, 0.45 milligrams, 0.625 milligrams, 0.9 milligrams and 1.25 milligrams. Sometimes these medicines are administered on a cyclic schedule--for example, 3 weeks on, 1 week off. It is generally advised to use the lowest effective dose for the shortest possible time. Estrogen appears to increase the risk of blood clots, heart attacks, strokes, and breast cancer. Also, when given without an opposing progestin in a woman with a uterus, they increase the risk of uterine cancer.
There are gels, sprays, and patches that administer the HRT drug through the skin. Products administered vaginally include creams, tablets, and rings which contain medicine. Dosing intervals range from once daily to once weekly except for the rings which are replaced every 90 days. Strengths range from 0.025 milligrams per day to 0.1 milligrams per day. The major risks and benefits of the topical forms and the oral forms are identical. In addition, the products applied externally may all cause skin redness and irritation.
These medications are used to prevent overgrowth of the lining of the uterus from estrogen therapy. This overgrowth increases the risk of cancer of the uterus. They are not typically used for HRT in a woman who has had a hysterectomy. Norenthindrone and various forms of the hormone progesterone are the most common drugs in this class. They can be taken as a separate pill, or in combination with an estrogen. These estrogen plus progestin products are available as tablets or skin patches. Potency, and therefore dosing, varies greatly. Sometimes the progestins are only added for part of the month in a cyclical fashion. The progestins as a group have the potential to cause vaginal bleeding, swelling, weight changes and breast tenderness.