Hormone replacement therapy uses synthetic hormones, which are hormones derived from plant and animal substances that are similar to hormones naturally produced in the human body, to treat the symptoms of menopause. Menopause occurs when a woman's ovaries stop releasing eggs, the menstrual cycle stops and the body produces fewer hormones. Because symptoms of menopause, such as hot flashes, night sweats, vaginal dryness, headaches and weight gain, can interfere with daily activities, many patients take medications to replenish hormone levels.
Prempro
Doctors commonly prescribe Prempro, the brand name for a medication containing conjugated estrogens with medroxyprogesterone acetate, to treat menopause. This single tablet medication contains estrogen derived from the urine of pregnant mares and a synthetic form of progesterone.
Although the body metabolizes and distributes the synthetic hormones found in Prempro similarly to natural hormones, the effects within the body are not exactly the same. Prempro effectively treats the symptoms of menopause, but a study conducted by the National Institutes of Health Woman's Health Initiative found that the risks of this medication outweigh the benefits.
Activella
Activella, another combination hormone replacement medication, contains estradiol and norethindrone. Estradiol is the most potent form of estrogen. Norethindrone inhibits the growth of the lining in the uterus. Although studies show that estrogen-only hormone replacement therapies increase the risk for endometrial cancer, the combination with a synthetic progestin--norethindrone--helps to reduce this risk, according to the American Cancer Society.
Provera
Provera, another common hormone replacement medication, contains only a synthetic form of progestin known as medroxyprogesterone. Medroxyprogesterone, like other synthetic progestins, prevents the overgrowth of the lining of the uterus. This mechanism of action makes Provera helpful in treating conditions of irregular menstrual cycles. In addition, doctors prescribe Provera to patients taking synthetic estrogen medications to help protect against uterine cancers. Provera, provided as a single tablet medication, should be taken once a day, according to the U.S. National Library of Medicine.
Premarin
Premarin, a vaginal estrogen cream, helps relieve vaginal dryness, itching and burning that often occurs during menopause. Although applied into the vagina, the synthetic estrogen hormone absorbs through the mucus membranes into the bloodstream, therefore altering blood hormone levels. Because synthetic estrogen increases the risk for endometrial cancer, doctors often prescribe a synthetic progestin along with Premarin, as described by the U.S. National Library of Medicine.
References
- MedLine Plus: Hormone Replacement Therapy
- National Institutes of Health Woman's Health Initiative: The Estrogen Plus Progestin Study
- American Cancer Society: Menopausal Hormone Replacement Therapy Cancer Risks
- U.S. National Library of Medicine: Medroxyprogesterone
- U.S. National Library of Medicine: Estrogen Vaginal
