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There are many types and forms of estrogen available for menopausal hormone replacement in the United States. These include tablets, injections, creams, patches, pellets, and vaginal inserts. There are advantages and disadvantages to each method. No one method is perfect for everyone. Let’s look at different therapeutic approaches to menopause. First, tablets. The following estrogen tablets are available in the United States: Tablets: available dosages (mg)
The "gold standard" for many years has been Premarin®. This is available in a wide range of dosages. In mid 1999, a new form of conjugated estrogens (Celestin®)derived from plant sterols (soy) was released in the US. Although biologically it is identical to the conjugated estrogens derived from animal sources (pregnant mare's urine), some individuals may prefer to use it for ideological reasons. Although the 0.625mg dose is standard for most women, it probably is better to start a younger woman, especially if their ovaries have been surgically removed on a higher dose such as 1.25mg. Elderly women starting Premarin® for osteoporosis management after many years of estrogen deprivation probably should start with a very low dose such as 0.3mg. Estrace® is estradiol - the natural estrogen. Like all "natural hormones, absorption may be more difficult so more may be needed to get the same therapeutic effect. Oral estradiol has a shorter half-life than other forms of estrogen so it may need to be taken twice a day. Recently, however, this form of estrogen has become available generically in the US. One of the advantages to this form, as a generic, is that it is much cheaper than the brand name and quite comparable in terms of effectiveness. Because of its short half life in the blood (about 4 hours), it is better to take it in the evening to avoid night-time sleep problems. Raloxifene (Evista®) is an entirely new form of estrogen called a SERM or selective estrogen receptor modulator. It appears to protect from breast and uterine cancer while protecting bones and the heart. Tamoxifen(Zoladex®) is an older SERM which has been used for many years for adjuvant therapy in breast cancer. It causes a dramatic reduction in the risks from breast cancer while protecting bones and the heart. Gynecologists do not care for Tamoxifen because it stimulates the lining of the uterus and may increase the risk for uterine cancer. Since both Raloxifene and Tamoxifen commonly causes severe hot flashes, it is a poor choice for a woman in the throes of acute menopausal symptoms. Unfortunately, there appear to be a group of woman who have problems absorbing estrogen tablets. Estrogen taken by mouth has to pass through the liver before reaching estrogen sensitive tissues. The liver contains enzymes which can inactivate the estrogen before it even reaches the places in the body where it is supposed to work. The liver also produces substances (sex hormone binding globulins) which also inactivate other sex hormones such as testosterone. This can effect libido. The liver can also increase substances in the blood which can cause of very slight increase in the risk of stoke and blood clots. Unfortunately, there are many women who take estrogen for many years and her physician fails to determine if it is really doing anything. Tragically, she does not derive the benefit from the medication she is faithfully taking. Ways in which the clinical effectiveness of estrogen can be judged include the presence of menstruation, effects of vaginal tissue and cervical mucous, the Pap smear, or biochemical measurements. Estrogens are also available in combination with progesterone. This is a convenient packaging since one takes only one pill a day instead of two.
With the exception of Prempro®, these other choices have not been extensively studied and it is assumed that they carry the same risks as Prempro®. The WHI study showed a very small increased risk of stroke and breast cancer associated with Prempro®. The risk of fractures and colon cancer was reduced. An alternative to tablets are skin patches. The original patch, Estraderm®, caused a lot of skin problems, particularly in the summer or in sub-tropical areas. The newer patches are much better. Vivelle dot® offers a wider ranges of dosages than Climera®. Climera® is used once a week which is more convenient but many women prefer the twice a week dose of Vivelle dot® since the patches become soiled or may even fall off if they get wet repeatedly. 0.05 is the equivalent of 0.625mg of Premarin®. Unfortunately,a generic patch which is huge and ugly has been distributed as a substitute for Climera®. Obviously, the delivery system cannot be the same yet the FDA generic drug division has approved this. If your pharmacist attempts to substitute a huge flesh colored patch for a lovely small transparent patch, protest that it is not the same. Patches available dosages (mcg)
Women who have a uterus cannot use estrogen only patches safely. There are combination patches using the same technology as Climera® and Vivelle dot®. They are
The French manufacture a product called Estradose® in which estradiol is packaged in a transdermal gel which disappears into the skin almost immediately after application. The manufacturer recommends that two plungerfuls be applied to the arms and shoulders daily. There is a comparable American product called Estrogel® which is comparable. The current recommended dose is 1 pump daily. Many years ago, physicians recognized that there were a group of women who failed to get a satisfactory outcome from oral estrogen. They would get a simple injection every three weeks. This method has been criticized, often unfairly. For some women, estrogen injections have markedly improved their lives. The main problems are the marked variation is blood levels (very high after the injection and then dropping) and that some women become almost addicted to these injections. It can be mixed with small amounts of testosterone if needed. Injections available dosages (mg) Estradiol Cypionate 5 mg/ml 10 ml vial, give 1-1 ½ cc every 3-4 weeks IM Estradiol Valerate 40 mg/ml 10ml ml vial,give 1-1 ½ cc every 3-4 weeks IM Some women are reluctant to take estrogen because they do not like the side effects, are afraid of breast cancer or cardiac risks or they are afraid to put "something" in their bodies. However, they are having problems with either urinary incontinence or vaginal irritation due to lack of hormones. Estrogen is available as a vaginal cream- conjugated estrogen (Premarin®) or estradiol (Estrace®). It can be applied with a vaginal applicator. Small amounts of the estrogen will be absorbed so some patients, especially if using larger dosages, will still notice some side effects. Another way of administering estrogen vaginally uses a silastic ring saturated with estrogen. It is called Estring®. It can be left in place for up to 3 months. It has the advantage of not being as messy as the creams. For very elderly patients, it eliminates compliance problems. However, it is not a substitute for systemic estrogen therapy in terms of protection from osteoporosis or perhaps Alzheimer’s disease. Finally there is a vaginal tablet (Vagifem®) which can be placed in the vagina biweekly for management of atrophic vaginitis. Estradiol pellets 25 mg 2-4 every 3-5 months has been experimental for about 20 years. The use of estrogen in this form is not approved by the U.S. Food and Drug Administration. It is relatively simple to manufacture using pure estradiol which has been available in the United States for many years. However, there are only a few endocrinologists in the United States who have access to them. These pellets are available here in Atlanta. They are placed under the skin through a needle. They offer the advantage of very consistent blood levels without the problems of pills (unpredictable absorption, remembering to take them), patches (skin irritation), injections (markedly variable blood levels), or vaginal creams (unpredictable absorption). For many women in whom all other forms of estrogen have failed, these pellets have been a godsend. These can be obtained from Cathy Crowley at the Pavilion Compounding Pharmacy, 3193 Howell Mill Road NW, Atlanta GA 30327. 404 352-5780. Her E-Mail address is pcompound@bellsouth.net and her website is www.pavilioncompounding.com. A special needle and trocar are needed to insert these and it should be done only by a trained physician. For more information about pellets, please check out our webpage on Hormone Pellets. Phytoestrogens are so called "natural estrogens" found in soy and other vegetable sources. These are not the same estrogen (estradiol) which the human body produces. In truth, all estrogens marketed throughout the world today other than Premarin are derived from vegetable sources. Modern pharmacological manufacturers modify the naturally occurring molecule to imitate human estrogen, to make it more absorbable, to lengthen its biological life, to make it more potent (so that you have to take less), and to remove undesirable side effects and impurities.
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