Health officials in the United States have issued a warning regarding so-called "bio-identical" hormone therapy (BHRT).
The Food and Drug Administration (FDA) says claims being made about the safety and effectiveness of "bio-identical" hormones were false, misleading and are not supported by medical evidence.
The drug watchdog has warned seven pharmacy operators about claims they are making which suggests their hormone products are superior to approved menopause therapies and that they could be used to prevent and treat serious conditions such as Alzheimer's, strokes and cancer.
Such drugs contain hormones such as estrogen, progesterone and estriol which is not a component of an FDA-approved drug and has not been proven safe and effective for any use.
Marketing strategies imply that the BHRT drugs are natural or identical to the hormones made by the body and the FDA is concerned that these claims mislead patients, as well as doctors and other health care professionals.
Drug company Wyeth, which sells FDA-approved hormone replacement therapy, petitioned the agency to take action against makers of bio-identical hormones.
Bio-identical hormones are made by so-called compounding pharmacies that tailor make medicines to particular patients when doctors believe approved HRT products are inappropriate.
The warning letters state that the pharmacy operations violate federal law by making false and misleading claims about their hormone therapy drugs.
The International Academy of Compounding Pharmacists says the FDA's action means many women will be denied access to products that may help them when approved therapies have failed.