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Editorial label review

Alloy side effects: hair loss

Primary formulary: Estradiol (oral and patch) + oral micronized progesterone; oxybutynin ER for vasomotor symptoms

Quick answer

Hair loss shows up on the FDA labels for the active ingredients Alloy prescribes — Estradiol (oral and patch) + oral micronized progesterone. This page walks through the labelled frequency ranges, what to watch for, and when to call your clinician.

What Alloy prescribes and why it matters for hair loss

Alloy prescribes FDA-approved bioidentical estradiol and oral micronized progesterone, plus oxybutynin ER as a non-hormonal option for vasomotor symptoms. Because Alloy prescribes FDA-approved active ingredients, the labelled adverse-reaction tables from those medications describe the frequencies you should expect. The progestin component (micronized progesterone) is the primary label source for alopecia signals across all four programmes.

Common label-level side effects

Sourced from Section 6 (Adverse Reactions) of each FDA-approved PIL.

  • Alopecia is listed as an uncommon reaction (< 1%) on the Prometrium micronized-progesterone PIL Section 6.2 post-marketing table
  • Estradiol PILs list hair loss and hirsutism at low frequency (< 1%) in Section 6 combination-therapy adverse reactions
  • Telogen-effluvium-style shedding described anecdotally when dose or delivery route changes; not treated as a labelled ADR

Serious label-level warnings

Drawn from Section 5 (Warnings and Precautions) of the FDA-approved PILs — including the estradiol boxed warning where applicable.

  • Rapid patchy hair loss with rash — the Prometrium PIL flags rare hypersensitivity reactions to review promptly
  • Hair loss combined with new fatigue and weight change — evaluate thyroid function before attributing to HRT

When to contact your clinician

Contact your clinician if shedding is patchy, painful, or paired with a rash — the Prometrium label lists these as hypersensitivity signals requiring assessment.

Call 911 if you develop chest pain, one-sided weakness, sudden severe headache, vision or speech change, or shortness of breath — per the estradiol PIL boxed warning for cardiovascular events.

What to ask your provider

  • “Which SKU in the Alloy formulary am I on, and what is its labelled frequency for hair loss?”
  • “Is my hair losslikely a labelled adverse reaction, or something separate that needs its own workup?”
  • “Would a different delivery route (patch vs. pill, oral vs. transdermal) change my expected frequency?”
  • “What is the plan if hair lossdoes not settle within 2–3 cycles?”

Frequently asked questions

How often does hair loss happen on Alloy?
Alloy's primary regimen — Estradiol (oral and patch) + oral micronized progesterone; oxybutynin ER for vasomotor symptoms — carries the FDA-labelled adverse-reaction frequencies for hair loss described on this page. Ranges vary from < 1% to 45% depending on the specific active ingredient and delivery route. See the sources block for the exact PIL tables.
When should I stop Alloy because of hair loss?
Talk to your clinician immediately if you meet any of the "when to contact" criteria on this page — most estradiol PIL Section 5 warnings require prompt reassessment. Do not stop hormone therapy without medical input; abrupt discontinuation can trigger rebound symptoms.
Is hair loss on the FDA label for Alloy's medications?
The progestin component (micronized progesterone) is the primary label source for alopecia signals across all four programmes.
Is hair loss caused by menopause itself?
Hair loss can appear during the menopause transition for reasons unrelated to hormone therapy. Our /does-menopause-cause/hair-loss explainer covers what the underlying biology is and how clinicians disentangle the transition from the treatment.

Sources

  1. FDAFDA-approved label — Estrace (estradiol) via DailyMed
  2. FDAFDA-approved label — Vivelle-Dot (estradiol transdermal) via DailyMed
  3. FDAFDA-approved label — Prometrium (micronized progesterone) via DailyMed