“Bio-identical” Hormones

Introduction

Women and health professionals are constantly being given information about ‘hormone imbalance’ and how to deal with menopause ‘naturally’. All this information should be carefully evaluated, giving consideration to its accuracy, and the reputation and vested financial interests of the group promoting the information.

Many women are turning away from approved pharmaceutical postmenopausal hormone therapy (HT) currently available as a tablet, patch, gel and/or implant and are using instead hormonal preparations made up as lozenges or troches or creams. These preparations are sucked in the cheek and are absorbed through the lining of thek cheek or through the skin.

The makers of these hormone preparations have stated that they are natural ‘bio-identical’ hormones. This description has been deemed to be “a marketing term that carries no scientific or medical merit” (U.S. Food and Drug Administration 2008) It may also be misleading as it implies they are non-synthetic. ‘Bio-identical’ hormones are all manufactured synthetically by a similar process as are most hormones including the pill. The process begins with a chemical substance from either the yam or soy. The hormones, once synthesised, are in forms that are produced in the body.

Compounded preparations

Compounded ‘bio-identical’ hormone preparations also require a doctor’s prescription and are made up by pharmacists who call themselves compounding pharmacists. There are no further training requirements for compounding pharmacists, who are likely to have had the same training as your family pharmacist.

The pharmacists making the ‘bio-identical’ preparations are not required to adhere to the codes of conduct of the professional pharmaceutical body, Medicines Australia, as these codes apply only to pharmaceutical companies. This means there is limited formal quality control or quality assurance on individual formulations. There has also been no formal research into dosage and the dose prescribed is the responsibility of the prescribing doctor.

Hormone formulations made in a pharmacy are expensive as they are individually prepared. The government department responsible for the approval of medicines is the Therapeutic Goods Administration (TGA), which requires vigorous safety and effectiveness data before approving any medications. But ‘bio-identical’ formulations are not subject to TGA rules, as they are compounded by pharmacists and not made by pharmaceutical companies.

Doctors prescribing ‘bio-identical’ HT monitor dosage by performing tests on the hormone levels in the saliva or blood; however, there is little correlation between blood levels and menopausal symptom relief and this practice is not based on evidence and is discouraged by academic specialist societies internationally.

About the hormones including oestrogen

The oestrogen present in many oral and all non-oral hormone therapies is the same oestrogen that occurs naturally in the human body – oestradiol, the same oestrogen preparation as most government-approved oral and non-oral hormone therapies (such as patches, implants and gels). It is misleading to suggest that these troches or lozenges and creams have advantages over TGA approved pharmaceutical oestrogen therapies.

The hormone preparations made in a pharmacy may contain a mix of the three major classes of oestrogen in the female body: oestradiol, oestrone and oestriol. There is no evidence to support that giving oestrogen in this way is better than giving oestradiol alone. It should be noted that our bodies automatically make the other two oestrogens from oestradiol.

Oestrogen mixes are sometimes combined with progesterone, testosterone or DHEA (a hormone made by the adrenal glands) or they can be each prescribed alone. Of note, DHEA is not approved for use in Australia by the TGA. Progesterone is not used in conventional pharmaceutical HT as it is filtered by the liver, therefore altered progestin compounds are used.

Safety and efficacy

We have no research evidence that the recommended doses of the hormone preparations made by compounding pharmacists are safe or effective. Currently there is no published data for these products, yet documents recommending various doses and equivalent doses to TGA-approved oestrogen therapies have been issued. It is important to note that these are not evidence based. It is also important to note that there is no adequate data to show what dose of progestin (progesterone) is necessary to protect the lining of the uterus (endometrium). No evidence is available from any published study to show that progesterone absorbed through the cheek will protect the lining of the uterus from conditions such as uterine cancer.

It has been claimed this form of HT does not cause side effects. This is unproven and unlikely, with many women presenting with known complications of oestrogen and testosterone therapy while on ‘bio-identical’ hormonal preparations. Blood levels of hormones can also be very elevated on troches therapy and until further research is done, women need to be cautious.

Summary

There are theoretical advantages to the use of hormonal preparations similar to the forms produced in the body, and in future, these preparations may be included in regulated HT; however further research and regulation is needed. Prescription of so-called ‘bio-identical’ hormones cannot be recommended until there is sound pharmacokinetic, efficacy and safety data.

These are the fundamentally similar hormones to HT but given in a different way and we would expect them to convey similar risks to conventional pharmaceutical HT, potentially though, side effects may be exacerbated as appropriate doses are not known.

Some health practitioners are promoting ‘bio-identical’ hormone therapy not only as safe, but also as preventing cancer. There is no published evidence that this is true and women should be cautious about taking any hormonal preparations that have not been subjected to careful research evaluation.

Recent Developments: January 9, 2008

The U.S. Food and Drug Administration (FDA) announced that it has begun enforcement action against compounding pharmacies making false and misleading claims about the safety and efficacy of ‘bioidentical hormones’. The FDA also announced that it considers the term ‘bioidententical’ a marketing term and not one of scientific or medical merit.  FDA officials stated that claims made about safety and efficacy of compounded ‘bioidentical hormones’ are false and misleading, with no credible scientific evidence to support them.  The FDA has now posted a Consumer Update, titled “Bio-identicals: Sorting Myths from Facts”. The new online publication also provides links to long-standing information available on the website.