Two main types of estradiol injections are used to treat low estrogen levels in women and advanced prostate cancer in men. The main difference between the two involves ingredients added to the estradiol injections. Estradiol cypionate contains the E-2, also called 17B, form of estrogen and has cottonseed oil. Estradiol valerate is made with sesame seed oil and is the form generally used in male-to-female sex-change procedures. Both forms of estradiol injections can be used to treat similar conditions.
Three types of estrogen are produced in the human body as sex hormones. E-2 hormones are the most dominant and are secreted by the ovaries in women who are not pregnant, the testes in men, and the brain in both sexes. This sex hormone regulates female menstrual cycles, with levels highest before eggs are released by the ovaries. This hormone helps the ovulation process and fertilization of eggs by male sperm. It might also regulate cholesterol levels and create strong bones.
Estradiol cypionate injections represent the E-2 form of estrogen, also called oestradiol. Injections bypass the liver to improve absorption rates. It is used to treat symptoms of menopause, advanced prostate cancer, and some breast cancer symptoms. Estradiol cypionate injections might also help infertile women become pregnant.
E-1 estrogen converts estrone to estradiol in children as they reach puberty, causing levels to rise. This sex hormone also regulates the menstrual cycle in women, rising and falling each month. A pregnant woman produces substantial levels of E-3 estrogen in the placenta. Levels of E-2 and E-3 fall dramatically after menopause.
Doctors use estradiol injections as hormone replacement therapy in women who suffer hot flashes, vaginal dryness, and other troublesome effects of menopause. Injections are usually given once per month to ease symptoms and protect bones from becoming thin and brittle. It is not used in pregnant women because it might cause birth defects.
Estradiol valerate injections might be used by men seeking a more female appearance. It typically causes breasts to develop and reduces the size of testes and the prostate gland. Men receiving estradiol injections might develop softer skin and see a decrease in body hair as levels of testosterone decline and estrogen levels increase. The drug typically reduces the sex drive and aggressiveness.
Physicians commonly advise using hormone injections at the lowest dose possible for short periods of time. These drugs increase the risk of endometrial cancer, breast cancer, and dementia in women over the age of 65. They also might cause blood clots and strokes in post-menopausal women. Some hormone replacement therapy drug manufacturers add progestin to reduce these risks.
Side effects are also common with estradiol injections, which include pain or enlargement of breasts. Changes might occur in the menstrual flow of younger women, which could include cramping. These drugs might also increase the risk of gallbladder or pancreatic disorders. Some people using estrogen injections report mood changes and depression, along with weight gain or loss.