Misconception and Concerns about Bioidentical Hormones Used for Custom-Compounded Hormone Therapy

The results of the Women’s Health Initiative hormone therapy (HT) trials have caused both apprehension and confusion about the overall risks and benefits associated with postmenopausal HT (1). Since the results were published, patient and clinician interest in potential alternatives to conventional HT has grown immensely and continues to grow. This appears to be particularly true for products or regimens that claim to have fewer risks and side effects than commercially available HT preparations. One commonly used alternative HT involves customcompounded hormone preparations. The hormones in these preparations include estrogen [17 -estradiol (estradiol), estrone, and/or estriol], progesterone, testosterone, androstenedione, and dehydroepiandrosterone. The products can be prepared in individualized dosages and forms such as creams, gels, lotions, sublingual tablets, troches (lozenges) for buccal administration, and suppositories by compounding pharmacies from a clinician’s prescription. They are often touted by advocates as safer than commercially prepared HT products. Proponents also claim that customcompounded HT is associated with fewer side effects and may provide better symptom relief than conventional HT because the hormones used in the preparations are “bioidentical,” i.e. identical to those made in the body. The majority of these claims are unsubstantiated, and no rigorous randomized control trials have been carried out to support any of the claims. Because the customcompounding of HT products is not regulated, a particular concern is that some women may be overdosed, or treated with ineffective products, or subject to unidentified risk. The objectives of the present commentary are: 1) to show that the so-called “bioidentical” hormones in custom-compounded HT preparations may not be identical to those made in the body; and 2) to point out how the lack of regulation of these hormone products can cause adverse effects in postmenopausal women using them.