HRT-What hormones are used and how to take them
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What Hormones Are Used in HRT?

HRT typically includes some type of estrogen, and, if a woman has an intact uterus, natural micronized progesterone or, more commonly, a progestin (a drug with progesterone-like actions on the uterus) to prevent endometrial cancer.

Estrogen replacement therapy (ERT) refers to taking some form of estrogen alone. Estrogen taken by itself is also referred to as unopposed estrogen—meaning that no progesterone or progestin is taken to counteract the effects of estrogen on the uterus. Unopposed estrogen can cause endometrial cancer (cancer of the lining of the uterus). ERT is an option mainly for women who have had a hysterectomy (removal of the uterus).

Women with symptoms during perimenopause might decide to take low-dose birth control pills (which contain both estrogen and progestin). Some women may benefit from taking natural progesterone alone, or progesterone combined with a low dose of estrogen. A low-dose estrogen patch works particularly well to provide a steady amount of estrogen, preventing the wide swings in estrogen levels that many women experience during perimenopause.


The Women's Health Initiative (WHI) study

This major federally funded study included an HRT component that compared Prempro (pills containing conjugated equine estrogens, or Premarin, and medroxyprogesterone, a progestin) to placebo. The WHI study was stopped 3 years early in July 2002 due to the finding of an increased risk of breast cancer in the women taking Prempro. In addition, the study found that the women taking Prempro had more heart attacks, strokes, and blood clots than those taking the placebo pills. However, study results also suggest that the therapy reduced the risk of colorectal cancer and bone fractures. An estrogen-only (using Premarin) arm of the study is continuing. For more information about the WHI study along with updated HRT recommendations, visit National Heart, Lung, and Blood Institute.


How Is HRT Taken?

conventional hormone replacement drugs

In the United States, the most frequently prescribed estrogen product for HRT is conjugated equine (horse) estrogens (brand name Premarin). The most frequently prescribed progestin for HRT is medroxyprogesterone acetate (MPA).

bio-identical hormones COMPOUNDED

There are many alternatives to conventional drug products, including natural or bio-identical hormones, which are identical in chemical structure to the hormones naturally produced by our bodies. This type of HRT is referred to as natural hormone replacement therapy, or NHRT.

NHRT is available both in brand-name products and from compounding pharmacies, which can supply any of the bio-identical hormones alone or combine them into one dose in the form desired (e.g, sublingual tablets, oil caps, or cream).

HRT is usually taken in one of two regimens:

  1. Cyclical, or cyclical combined, HRT: estrogen is usually taken every day of the month, and progestin/progesterone is added for only part of each month. This is also referred to as a sequential HRT. It is meant to mimic the natural menstrual cycle and typically causes bleeding similar to a period after the progestin/progesterone is stopped.

  2. Continuous, or continuous combined, HRT: estrogen and progestin/progesterone are both taken every day. While there is usually no "period," some spotting or bleeding may occur occasionally, especially in the years right after menopause. Spotting or bleeding can sometimes be corrected by adjusting the dose, the regimen, or the type of hormone products used.

Sometimes other schedules, such as continuous estrogen with intermittent progestin/progesterone, are used. Your healthcare provider can help you decide what regimen is right for you.

Dosages prescribed for ERT, HRT and NHRT vary and can be adjusted to meet a woman’s specific needs. Relatively low doses of estrogen and estrogen/progestin have been found to be effective for treating symptoms of menopause and can also maintain bone density. Low doses of estrogen found to be effective in recent studies include, for example, doses of conjugated equine estrogen (Premarin) as low as .3 mg (compared to the "standard" dose of .625 mg) alone or combined with a reduced dose of progestin; doses of oral estradiol as low as .25 mg; and a transdermal patch dose of .025 micrograms. Using lower doses of estrogens and progestins also reduces side effects from the drugs.

There are dozens of possible ways to take HRT, and ideally, hormone therapy should be tailored to your particular needs. Talk with your healthcare provider to learn more about HRT benefits and risks in order to choose what options might be right for you. A compounding pharmacist is also able to answer questions regarding hormones and HRT.

Alarming News! - FDA Bans Estriol

The FDA announced on January 9, 2008 that the hormone estriol can no longer be used in estrogen medications customized for women by compounding pharmacies. Estriol is a component of 90 percent or more of these customized preparations.
Monday, 14th January, 2008 excerpt from elixir news:

Doctors condemn FDA decision to ban estriol following pressure from drug lobby

"The FDA claims that it is taking estriol off the market because it is not a component of any FDA approved drug, despite the fact that the hormone has been used for decades without problems. Estriol has a long standing United States Pharmacopoeia monograph, an accepted standard for drug ingredients absent significant health risks. Other common drugs that are not components of FDA approved drugs include aspirin.

"The FDA action is in response to a "citizen petition" filed by the giant drug maker Wyeth Pharmaceuticals. Wyeth is the maker of Premarin and Prempro, two hormone treatments for women that have been linked to cancer, heart disease and stroke by a 2002 Women's Health Initiative, National Institute of Health (NIH) study. Millions of women have discontinued taking Wyeth's hormone products as a result of the WHI study, which was halted because of the serious health risks that were discovered in 2002.

"The FDA has succumbed to pressure from Wyeth in its attempt to clear the market of safer alternatives to its unsafe products," said Erika Schwartz, M.D., a co-founder of BHI, the Bioidentical Hormone Initiative, a not-for-profit medical organization comprised of conventionally trained, practicing physicians who have successfully treated patients with bioidentical hormones for years.

"The FDA should protect the interest of women, not the profits of Wyeth."

The campaign to discredit compounded bioidentical hormones enrages physicians.

January 14, 2008 excerpt from Bioidentical Hormone Initiative:

The BHI physicians, a coalition of gynecologists, internists, allergists, ER physicians and general practitioners who do not have a direct financial stake in the issue and who bring valuable and insightful information, provide a review of the medical literature demonstrating how natural hormones are superior to their synthetic counterparts. "The conclusion is clear that bio-identical hormones are a safe alternative to Premarin and medroxyprogesterone acetate (MPA), marketed as Provera. The natural bio-identical hormones are very different from their synthetic versions, often having completely opposite physical and cellular effects.

"Thus, it is critical that women be given the information that these natural hormones do not have the negative side effects of the synthetic hormones and in no way pertain to the conclusions reached by the Women's Health Initiative (WHI) study. Natural hormones are a safe and more conservative approach to hormone replacement therapy that does not carry the risks associated with Premarin and Provera.

"There are no legitimate medical, scientific or legal reasons for the FDA to take this action," said Dr. Schwartz. "It would require countless women to return to their doctors and alter the medications they have used both safely and effectively for years. If the FDA has its way, since estriol is available in Europe, a woman will need a passport, not a prescription to get her medication.

"The citizen petition filed by Wyeth with the FDA requested that estriol be removed from the market, along with other requests to remove customized medications that compete with their flawed products. The petition created a tremendous backlash from women, doctors and pharmacists. Over 77,000 comments, a near record, were filed with the FDA in response to the petition, all but a handful opposing Wyeth's request.

"The few comments in support of the Wyeth petition were filed mostly by organizations with substantial financial ties to Wyeth," said Dr. Schwartz. "The FDA has chosen to protect Wyeth's wealth rather than women's health. This is a shameful act for this agency to take.”


On January 9, 2008, FDA took action to impose harmful restrictions on the compounding and dispensing of bio-identical hormone replacement therapy (BHRT), specifically compounded medicines containing the drug estriol. This action has critical implications for pharmacists, patients and physicians.

You can learn more about the problem from the compounding pharmacists' point of view by clicking here.

Should you care to oppose the FDA's Action to Restrict BHRT, click here to visit a website that provides more information and ways to take action.


Please read on...

  What Is Hormone Replacement Therapy (HRT) and Why Would I Need It?
   What Hormones Are Used in HRT? and How Is HRT Taken?
About Estrogen
  About Progesterone
  Benefits, Risks and Side Effects of ERT, HRT, and NHRT
  HRT and Breast Cancer
  Androgens, SERMs and Other Drugs for Menopause
  What Are Some Alternatives to Standard HRT?
  Resources and References


Page uploaded September 2002, Updated March 2008






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Updated 09/29/2010