In this episode of The Thyroidless Life, Dr. Rebecca Warren delivers a sharp, science-driven breakdown of why the timing of your thyroid medication before labs can completely distort your results—and your treatment. She explains the two pharmacokinetic phases of T3, why the early post-dose spike is not a true reflection of tissue-level thyroid status, and how mistimed labs routinely lead to misdiagnosis, under-treatment, or dangerous dose changes. Drawing from clinical experience, research interviews, and two decades of living post-thyroidectomy, Dr. Rebecca shows why fasted labs are essential. If you've ever been told your labs "look fine" while your symptoms scream otherwise.

Studies mentioned:

Study 1: Single Dose T3 Administration: Kinetics and Effects on Biochemical and Physiologic Parameters
https://pmc.ncbi.nlm.nih.gov/articles/PMC5167556/

Study 2: Daily Administration of Short-Acting Liothyronine Is Associated with Significant Triiodothyronine Excursions and Fails to Alter Thyroid-Responsive Parameters
https://pmc.ncbi.nlm.nih.gov/articles/PMC4913511/

Study 3: Pharmacokinetics of L-Triiodothyronine in Patients Undergoing Thyroid Hormone Therapy Withdrawal
https://pmc.ncbi.nlm.nih.gov/articles/PMC6797066/

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Next steps

► Get your FREE Optimal Thyroid Labs eBook: https://www.drswarren.com/thyroidlabsguide
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► Order your own thyroid labs here: https://www.ultalabtests.com/partners/drswarren

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 ⚠️ Disclaimer 

The content of this podcast is for informational purposes only and is not intended as medical advice. Always consult a healthcare professional for any health concerns and before making any changes to your medications. The views expressed in this podcast, including those of Dr. Warren, do not constitute medical advice. The podcast and its host are not liable for any adverse effects resulting from information provided. Opinions of guests are their own, and the podcast does not endorse or assume responsibility for guest statements. Guests may have interests in products or services mentioned. If you have a medical issue, seek the advice of a licensed healthcare provider.