Bioidentical hormones are often promoted as “natural” or “chemical free” hormones, and the implication is that they are safer than FDA-approved hormone medications. However, the FDA and the Endocrine Society consider the phrase “bioidentical hormone therapy” to be a marketing term and not one based on scientific evidence.
- Many forms of bioidentical hormone therapy are compounded recipes prepared by a compounding pharmacy and are not FDA approved.
- Compounded preparations are personally tailored and have not been rigorously tested to prove the active ingredients are absorbed properly or that they will provide predictable levels of the hormone(s) in the body.
- The potency, quality, and purity of compounded hormone preparations are not guaranteed.
The National Academies of Science, Engineering and Medicine reported in 2020 that individually prepared bioidentical hormones may not be better or safer than FDA-approved therapies. In FDA tests, bioidentical hormone mixtures from compounding pharmacies failed potency testing at far higher rates than FDA-approved drug therapies. This variability means it is possible to both overdose and underdose on these preparations.
There are also no long-term studies regarding the use of compounded bioidentical hormone therapy so long-term effects are unknown.
What are Bioidentical Hormones?
Bioidentical hormones are man-made forms of hormones that are chemically and structurally identical to hormones naturally produced by the body. Bioidentical hormones, for example, estrogen, progesterone, and testosterone, usually come from plant or animal sources, and may sometimes be referred to as “natural” or “chemical free” hormones.
Some bioidentical hormones are U.S. Food and Drug Administration (FDA) approved, and others are formulas made by compounding pharmacies that are not regulated by the FDA.
What Are Bioidentical Hormones Used For?
Bioidentical hormones are often used to treat menopausal symptoms in women.
Bioidentical hormone replacement therapy may also be used to replace testosterone in men as they age, however, the FDA warns that prescription testosterone products are only approved only for men with low testosterone levels caused by certain medical conditions. Use of testosterone increases the risk of heart attack and stroke and it is not recommended to treat low testosterone levels due to aging.
Bioidentical hormone therapies approved by the FDA include:
- Estrogens (usually estradiol)
- Progesterone
- Pills: Prometrium
- Gel: Crinone
- Testosterone
What are Side Effects of Bioidentical Hormones?
All FDA-approved drugs must report side effects and these side effects are provided to consumers, however, compounded bioidentical hormone preparations are not required to have side effects reported. This does not mean they do not have any side effects.
There may be a higher risk of side effects with use of hormone pellet therapy. In one study, postmenopausal women using compounded bioidentical estradiol and/or testosterone pellet therapy experienced six times the number adverse side effects, including abnormal uterine bleeding and subsequent hysterectomy, compared to women using FDA-approved hormone therapy.
Common side effects of hormone therapy include:
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https://www.fda.gov/drugs/drug-safety-and-availability/fda-drug-safety-communication-fda-cautions-about-using-testosterone-products-low-testosterone-due
https://www.hormone.org/diseases-and-conditions/menopause/menopause-treatment/bioidentical-hormones
https://www.menopause.org/publications/clinical-practice-materials/bioidentical-hormone-therapy
https://www.healio.com/endocrinology/hormone-therapy/news/online/%7Bc3d60b3e-70a0-45d8-aa57-ca90b1e45800%7D/significantly-higher-side-effects-with-pellet-vs-fda-approved-ht
https://www.nap.edu/read/25791/chapter/1