Compounded vs FDA-approved HRT: what the difference actually means

Compounded hormone therapy is a $1.5+ billion industry in the US, marketed heavily as more "natural," "individualized," and safer than FDA-approved alternatives. The marketing is more confident than the evidence supports. Here's what the regulatory difference actually means.

What FDA approval means

An FDA-approved drug has been through standardized randomized trials demonstrating safety and efficacy for specific indications. The manufacturing process is inspected, dose accuracy is audited (typically required within ±10% of labeled dose), and post-market surveillance tracks adverse events at population scale. Generic equivalents must demonstrate bioequivalence to the brand. Examples in HRT: Estrace, Climara, Vivelle-Dot, Prometrium, Vagifem, Estring, Premarin.

What compounding means

A 503A compounding pharmacy mixes a drug to specification under an individual prescription. Compounding is regulated by state boards of pharmacy and (loosely) by the FDA, but compounded drugs themselves are not FDA-approved. Dose accuracy is not federally audited. Stability and potency are not federally verified. Adverse event tracking is not centralized. Examples: BiEst creams, custom progesterone troches, testosterone pellets.

The dose accuracy data

A 2014 NIH-funded study tested compounded estradiol creams from multiple US pharmacies. Doses ranged from 60% to 270% of what was labeled — a 4.5-fold variation in real-world potency. A separate 2017 study of compounded progesterone troches found similar variability. The American Society for Reproductive Medicine has cited dose variability as the central safety concern with cBHT, particularly because progesterone underdosing can leave the endometrium unopposed during estrogen therapy.

Why women choose compounded

Common reasons: a clinician recommended it (often a "BHRT specialist" — usually a marketing term, not a credential); marketing implying "individualized" hormone testing produces better outcomes (saliva and urine testing is not validated for this); insurance coverage isn't available for the FDA-approved form they want; need for a specific dose not commercially manufactured (rare); documented allergy to a non-active ingredient in FDA versions.

When compounding is appropriate

Narrow indications: documented inactive-ingredient allergy; a dose between FDA-approved increments that's clinically necessary; a delivery form not commercially available (some pellets); women whose insurance refuses FDA-approved options and who can't afford cash-pay. These cases exist but are a small fraction of cBHT prescriptions actually written.

The professional society stance

ACOG (2012, reaffirmed), NAMS (multiple position statements), and the Endocrine Society have all formally recommended FDA-approved hormone therapy over compounded for most women. The American Society for Reproductive Medicine has the strongest position — explicitly opposing the marketing claims around "individualized BHRT" and saliva-based hormone testing.

How to decide for yourself

If you're considering compounded HRT, ask your clinician: (1) Is there a specific reason an FDA-approved option won't work for me? (2) What dose accuracy data does this specific pharmacy publish? (3) How will we monitor endometrial protection if I have a uterus? (4) Is my insurance refusal final, or can we appeal? Most women starting HRT in 2026 have at least one FDA-approved option that fits — choosing compounded should be a deliberate decision with a clear clinical reason.

Informational only — discuss compounded vs FDA options with a clinician trained in menopause care.