They are marketed as "bio-identical" hormones or "bio-identical hormone replacement therapy," and they claim to do everything from helping menopausal women lose weight to preventing senility.
They are touted as safer and sometimes even more effective than conventional hormone-replacement therapy.
But the US Food and Drug Administration (FDA) warns that these claims are "unproven" and that the products are "potentially dangerous."
What's more, bio-identical hormone replacement therapy - or "BHRT" - is a "marketing term not recognized by FDA," the agency says.
Medical experts also are expressing some concerns about the products.
"We don't know anything [about these products]," says Dr. Suzanne Steinbaum, director of Women and Heart Disease at Lenox Hill Hospital in New York City. "This isn't FDA-approved. It's the same thing as a hormone. What concerns me is that people believe if it's not from a drug company, it's safe."
Dr. James Liu, chairman of the obstetrics and gynecology department at Case Medical Center, University Hospitals in Cleveland adds: "Over-the-counter products that are not listed as drugs can make some claims, and they have to be careful about it.
"Usually these are considered supplements. Suffice it to say, there is science behind some of what they say and a little bit of lack-of-science in other things," he says.
In October 2006, The Endocrine Society issued this position statement expressing concerns about these products: "'Bioidentical hormones,' particularly estrogen and progesterone, have been promoted as safer and more effective alternatives to more traditional hormone therapies, often by people outside of the medical community. In fact, little or no scientific and medical evidence exists to support such claims... Additionally, many 'bioidentical hormone' formulations are not subject to FDA oversight and can be inconsistent in dose and purity."
Since the release in 2002 of a Women's Health Initiative report, hormone replacement therapy (HRT) - used to relieve symptoms of menopause - has generated worrisome, and sometimes conflicting, headlines.
While linked to a reduced risk of colon cancer and fractures, the therapy has also been associated with an increased risk of breast cancer, stroke, blood clots, and heart attack. And so far, at least, there are no indications that HRT has any effect on preventing the development of dementia.
The concern over the potential risks of hormone-replacement therapy has allowed manufacturers of "natural products" to market supposedly better and safer versions of hormone therapy, according to the FDA.
They claim their products are identical to hormones produced by the body, and these "all-natural" pills, creams, lotions, and gels don't carry the risks of menopausal hormone therapies approved by the FDA.
Agency-approved HRT drugs are typically prescribed to treat symptoms of menopause, such as hot flashes and vaginal dryness.
But the FDA says it has not approved compounded "BHRT" drugs and cannot assure their safety or effectiveness.
Dr. Liu explains that "'bio-identical' really means that the structure of the compound you are claiming to be identical is biologically identical. It [the term] is applied primarily to female hormones that are used in hormone therapy."
But, Dr. Liu adds, "The main problem is how a woman would obtain [bio-identicals]. If it's pharmaceutical grade, FDA -grade, it's prescribed. It's just how it's made."
According to the FDA, some of the bio-identical hormones are "compounded," meaning they are mixed specially to meet an individual's needs. For example, certain dyes or preservatives may be eliminated if a person is allergic to them.
"The pharmacist assumes that responsibility and the physician should specify that on the prescription," says Dr. Liu. The bio-identical product may not have exactly the same ingredients as a standard product, he notes.
But be leery if a pharmacy claims that such compounded mixtures are safer or more effective than other hormone formulations, the FDA warns. They may not be mixed according to a licensed health-care professional's instructions.
"Women should be cognizant that both products have similar potencies, similar biological action, and similar side effects," explains Dr. Liu. "There's no reason to think bio-identicals are superior. There are either anecdotal or testimonial claims that one is better than the other. We're swayed by that as human beings."
Here are some points the FDA says to keep in mind:
• Approved hormone therapies are available by prescription only.
• Bio-identicals will have the same risks as the products they're identical to -- namely a heightened risk of breast cancer and serious heart problems. There may be other, as-yet-unknown risks, as well.
• Beware of claims that bio-identical products can be made based on hormone levels measured from a woman's saliva sample. Hormone levels fluctuate constantly. Saliva tests, which are FDA approved, are not specific enough to determine drug dosages.
• No drug containing the hormone estriol (the weakest of the three estrogens produced by the body) has been approved by the FDA. Only prescribers who have an investigational new drug (IND) application can compound drugs with estriol.
• In general, when using approved hormone-replacement therapies, the FDA and health care professionals recommend using the lowest dose possible for the shortest period needed.
Always consult your physician for more information.
When a woman reaches menopause, the production of estrogen and progesterone decreases significantly. HRT is a means of replacing these hormones that are no longer being produced by the body.
This type of therapy is usually initiated at or near menopause.
In years past, many physicians would recommend that women take HRT for the rest of their lives to obtain the maximum benefits; however, in light of the most current research, HRT is not advised for all women. The decision to take HRT needs to be made on an individual basis after a complete review of a woman's medical history.
The Women's Health Initiative recommends that women follow the US Food and Drug Administration (FDA) advice on hormone (estrogen-alone or estrogen-plus-progestin) therapy. It clearly states that hormone therapy should not be taken to prevent heart disease.
These products are approved therapies for relief from moderate to severe hot flashes and symptoms of vulvar and vaginal atrophy.
Although hormone therapy is effective for the prevention of postmenopausal osteoporosis, it should only be considered for women at significant risk of osteoporosis who cannot take non-estrogen medications.
The FDA recommends that hormone therapy be used at the lowest doses for the shortest duration needed to achieve the treatment goals.
Postmenopausal women who use or are considering using hormone therapy should discuss the possible benefits and risks to them with their physicians.
The National, Heart, Lung, and Blood Institute (NHLBI) offers the following suggestions for women who are deciding whether or not to use postmenopausal hormone therapy:
Because the study involved healthy women, only a small number of them had either a negative or positive effect from estrogen plus progestin therapy.
The percentages describe what would happen to a whole population - not to an individual woman. In the estrogen plus progestin therapy study the increased risk of breast cancer was less than a tenth of 1 percent each year.
When this risk is applied to a large group of women over several years, then the number of women affected becomes a public health concern.
The most important thing a woman can do in deciding to continue hormone replacement therapy is to discuss the current research with her physician and healthcare team.
Women need to be aware that taking a combined progesterone and estrogen regimen or estrogen alone is no longer recommended to prevent heart disease. A woman should discuss other alternatives of protecting the heart with her physician.
Women should discuss with their physicians the value of taking combined progesterone and estrogen replacement therapy or estrogen to prevent osteoporosis. There may be alternative treatments based on a woman's unique health profile.
Always consult your physician for more information.
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