Photo: Justin McManus

Women are being urged to avoid so-called natural hormone replacement therapy (NHRT), also known as bio-identical hormones, because of safety fears.

Two cases of uterine cancer in women taking NHRT have been referred to the Therapeutic Goods Administration in the past year by Dr John Eden, director of the Sydney Menopause Centre.

Dr Eden said the "hand-made hormones" were prepared by pharmacists known as "compounding chemists" without scrutiny.

Although the process is legal, it is beyond the regulatory control of the TGA and state-based pharmacy boards.

"There's a whole stack of women being treated out there with hand-made hormones. It's untested hormone replacement therapy," he said.

"Many women think they are getting a herbal treatment and are shocked to learn they are getting a hormone treatment."

Other women using NHRT have suffered elevated hormone levels. Side effects can include excessive bleeding, increased cancer risk and blood clots.

Alastair MacLennan, professor of obstetrics and gynaecology at Adelaide University and a leading commentator in the field, said the effects of the products were not known and their manufacture was not properly regulated. "My advice to women is not to consider using bio-identical hormones," he said. "It's a total con."

Natural hormone replacement therapy (NHRT) is prescribed by a few doctors and prepared by the compounding chemists on their own premises.

It is usually made into lozenges and there is no scientific evidence to support its use, experts say.

Like most conventional hormone replacement therapy, NHRT contains the female hormones oestrogen and progesterone, sourced from yams or soy and synthesised in laboratories.

However, NHRT can also include the male hormone testosterone, which is not approved in Australia for use on women.

It can also include thyroid hormone, little-understood sex steroid pregnenalone and DHEA, a steroid banned from manufacture in Australia. DHEA is unregistered and requires special approval. It cannot be marketed, yet some pharmacists spruik it as a miracle medicine.

Professor Helena Teede, research director at Australia's leading women's health organisation, the Jean Hailes Foundation, said many women using NHRT were unaware it was not formally approved by the TGA.

"Less than half of women will need drugs to help them through menopause, but for those who do there are proven alternative medicines and conventional hormone therapies. These compounded preparations are little understood and women taking them are essentially guinea pigs," she said.

Yet NHRT is marketed as safe and natural — an appealing alternative to women who have been bombarded with warnings, now largely considered exaggerated, linking conventional HRT to an increased risk of cancer.

Makers and suppliers of NHRT say it is safer than conventional therapies. They also claim it is more effective, as it is made specifically for each patient.

This approach has gained strong support from many women and their doctors, and leading specialists agree that if the process was properly managed it could provide a safe pharmaceutical alternative.

However, the practice now operates in a regulation vacuum, beyond the ambit of the TGA and the state pharmacy boards.

Some practitioners use saliva analysis, an unproven method, to determine women's hormone levels. Others diagnose and prescribe over the phone.

Sue Davis, professor of women's health, at Monash University, has seen many patients using NHRT with elevated hormones, including one with testosterone levels of 43, compared with a standard male range between 10 and 30. "This is hocus pocus stuff but with serious hormones," she said.

General practitioner Magdalena Simonis has also seen adverse reactions, including one patient with an oestrogen level of 3000 compared with a normal reading below 900, and another who needed surgery after developing bulky fibroids in her uterus.

NHRT's slick marketing rarely tells of such risks, experts warn.

"It's the pseudo-science that scares me. It's frightening and women are only being given half the story," Professor Davis said.

One of the largest enterprises, the Menopause Institute of Australia, and its director, Gary Aaron, will this month face in the Federal Court allegations of misleading and deceptive health claims.

President-elect of the Asia Pacific Menopause Foundation, Dr Elizabeth Farrell, said the industry, which is also booming in the US and Asia, was misleading women for commercial gain. NHRT can cost four times as much as conventional HRT.

"I object to the exploitation of women of my age. I find that absolutely appalling. It makes my blood boil and I'm enraged because women are misled," she said.

The industry is also booming in anti-ageing and veterinary preparations. Some pharmacists also make medicines for children, including remedies for attention deficit disorder.

Bert Frigo, owner of Compoundia, Melbourne's biggest compounding chemist, defended the practice, saying it filled a need for personalised medical care.

"All we are trying to do is provide a part of medicine that's been missing. One medicine doesn't fit all," he said.

He acknowledged the practice existed beyond the realm of evidence-based medicine, relying instead on "basic medical logic" and 20 years of anecdotal evidence from the US. He supports further regulation.

"It would be a good idea for the TGA and the pharmacy boards to work together to see if we can get a standard of compounding pharmacy," he said.

Frank Raue, general manager of the Professional Compounding Chemists of Australia — a network of compounding pharmacists and wholesaler of pharmaceutical ingredients, including hormones — would only answer questions by email.

The company defended the safety of the practice, but acknowledged there was no formal testing of the products: "Since compounded products are made on an individual basis according to the needs of a specific patient, it is not possible to test each product before supply to a patient without making the cost prohibitive. Many pharmacies do test samples of products that are made frequently."

Asked if they were concerned the products might be harmful to women, the company wrote that "any drugs, when used incorrectly, can be harmful", and added that there were also risks associated with conventional HRT.

In the United States, the Food and Drug Administration is attempting to regulate the compounding pharmacy sector. Concerns have also been raised about the manufacture of drugs by naturopaths and herbalists.