What are the FDA-approved bioidentical hormones and their dosing?

FDA-Approved Bioidentical Hormones and Dosing

There are no FDA-approved bioidentical hormone therapies specifically marketed as such, as "bioidentical hormone replacement therapy" is considered a marketing term rather than a formally defined drug classification according to the FDA. 1

FDA-Approved Hormones That Are Structurally Identical to Human Hormones

While the term "bioidentical" is not an FDA classification, the following FDA-approved hormone preparations contain molecules that are structurally identical to those produced by the human body:

Estrogens

• 17β-Estradiol (FDA-approved for menopausal symptoms) 2

  • Oral tablets: 0.5 mg, 1.0 mg, 2.0 mg daily
  • Transdermal patches: 0.025 mg/day, 0.0375 mg/day, 0.05 mg/day, 0.075 mg/day, 0.1 mg/day
  • Transdermal formulations are preferred due to lower rates of venous thromboembolism (VTE) and stroke 1

• Estropipate (FDA-approved for menopausal symptoms) 2

  • Oral tablets: 0.75 mg, 1.5 mg, 3.0 mg daily

Progestogens

• Micronized Progesterone (FDA-approved for menopausal symptoms and prevention of endometrial hyperplasia) 2
  • Oral capsules: 100 mg, 200 mg daily
  • May be preferred over medroxyprogesterone acetate (MPA) due to lower rates of VTE and breast cancer risk 1

Combination Therapies

• Estradiol/Norethindrone Acetate 3
  • Oral tablets: 1.0 mg/0.5 mg daily
  • Oral tablets: 0.5 mg/0.1 mg daily

Important Clinical Considerations

Safety and Efficacy

• FDA-approved hormone therapies have undergone rigorous testing for safety and efficacy, while compounded bioidentical hormones have not 1, 4
• The Women's Health Initiative (WHI) study primarily evaluated oral conjugated equine estrogen (0.625 mg/day) with or without oral medroxyprogesterone acetate (2.5 mg/day) 1

Compounded Bioidentical Hormones

• Custom compounded bioidentical hormones are not recommended because:
  • They lack FDA approval 4
  • Data supporting claims of superior safety and effectiveness are lacking 4, 5
  • There are concerns about dosing inconsistencies 5
  • Salivary hormone testing used to guide dosing lacks scientific validation 6, 5, 7

Clinical Applications

• For women with an intact uterus, estrogen must be combined with progesterone/progestin to prevent endometrial hyperplasia 3
• For women without a uterus, estrogen-only therapy can be used 3
• The lowest effective dose should be used for symptom management 1

Contraindications and Cautions

• Hormone therapy is contraindicated in women with:

  • History of hormonally mediated cancers 1
  • Abnormal vaginal bleeding
  • Recent thromboembolic events
  • Active liver disease
  • Pregnancy 1

• Use with caution in women with:

  • Coronary heart disease
  • Hypertension
  • Current smokers
  • Increased genetic cancer risk 1

Key Takeaways

• FDA-approved hormone preparations that are molecularly identical to human hormones exist, but the FDA does not classify or approve products specifically as "bioidentical"
• FDA-approved options are preferred over compounded formulations due to standardized dosing, quality control, and evidence-based safety profiles
• Hormone therapy should not be used for prevention of chronic conditions in postmenopausal women 1
• Transdermal estrogen formulations may offer safety advantages over oral formulations 1

Remember that hormone therapy decisions should be based on symptom management needs and individual risk factors, with the primary focus on morbidity, mortality, and quality of life outcomes.