Safety findings

Regulatory recordSupporting passage inspected

CYTOMEL carries a boxed warning against use for obesity or weight loss. Excess thyroid-hormone exposure can produce serious or life-threatening toxicity, particularly with sympathomimetic agents.^[1]

This warning does not mean appropriate thyroid replacement is equivalent to excessive exposure.

Inspection history

Clinical review: not reviewed by a qualified clinician.

2026-09-08 · Independent source inspection; applicability narrowed and inherited assertions excluded where unsupported. No qualified clinical review.

2026-09-09 · Independently reopened the current DailyMed label (SPL version 15, Effective Time 2026-05-18, the latest version as of access). Confirmed the boxed warning verbatim ("Thyroid hormones, including CYTOMEL, should not be used for the treatment of obesity or for weight loss"; "Larger doses may produce serious or even life-threatening manifestations of toxicity, particularly when given in association with sympathomimetic amines") and section 7.7 (Sympathomimetics). Noted the boxed warning's own cross-references are to sections 6, 7.7 and 10 rather than section 5, though section 5.1 separately discusses monitoring during concomitant sympathomimetic use; refined the supportLocations wording to section 5.1 for precision. No qualified clinical review.

Interaction evidence

Regulatory recordSupporting passage inspected

CYTOMEL labeling states that sympathomimetics may increase the effects of thyroid hormone or sympathomimetics; coronary insufficiency is a particular concern in coronary artery disease.^[2]

A drug-class label warning for oral liothyronine; not a clinical trial of each selected pair.
Caffeine, phenylpiracetam and all products tagged “stimulant” cannot automatically be treated as equivalent.

Inspection history

Clinical review: not reviewed by a qualified clinician.

2026-09-08 · Supporting passages inspected, scope corrected and legacy assertions reassessed; no clinician review performed.

2026-09-09 · Independently reopened every cited source afresh on 2026-09-09 (interaction batch, fresh deep-research pass); disposition and wording reconfirmed against the live sources, not carried over from the prior pass. No qualified clinical review.

Regulatory recordSupporting passage inspected

CYTOMEL labeling states that adding liothyronine (T3) therapy in patients with diabetes mellitus may worsen glycemic control and result in increased antidiabetic-agent or insulin requirements, and recommends monitoring glycemic control when liothyronine is started, changed or discontinued.^[2]

A drug-class label warning naming “antidiabetic agent or insulin requirements” generically, not a named insulin-analogue trial.
Does not establish a numeric hypoglycemia or hyperglycemia magnitude for this specific pair.

Inspection history

Clinical review: not reviewed by a qualified clinician.

2026-09-09 · New claim added 2026-09-09: while reopening CYTOMEL for ix-thyroid-adrenergic, independently found this separate, directly named T3/insulin label interaction (sections 5.5 and 7.2) that was not previously represented by any claim; proposed as a new documented-pair-strength addition.

What remains unresolved

Editorial assessment

These notes describe the scope of this review. Linked PMIDs are audit identifiers; an identifier alone does not verify a claim.

Narrowly supported passages published with study/product limits; remaining inherited assertions withheld from established-fact displays.

Not a comprehensive systematic review. Original monograph topics beyond the individual published claims—including monitoring schedules, contraindication lists, recovery assurances and detailed mechanisms—remain unverified.
No qualified clinician has reviewed these claims. Long-term outcomes and all marketed formulations have not been fully assessed.

This reference does not supply a dosing plan, monitoring timetable or recovery regimen. Discuss personal symptoms, medicines and laboratory results with a qualified clinician.

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References

CYTOMEL liothyronine: prescribing information
2026-05-18. Product label.
Inspected location: Boxed warning; sections 1, 5.1 and 7.7
Study context and inspection record
CYTOMEL (liothyronine sodium) prescribing information
2025-04. Product label.
Inspected location: Boxed warning; sections 5.5, 7.2 and 7.7
Study context and inspection record

Source inspection and clinical review are separate. An abstract check is not a full-text review. The records above identify what was actually inspected and do not certify the complete literature.

Recorded verification attempts

Fresh PubMed EUtils retrieval for inherited lead PMID 33777817; identity, abstract and linked corrections checked where an abstract existed.
https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=51452b31-ff68-4e0c-b982-c15502ebf1d3 — label; Boxed warning; sections 1, 5 and 7.7

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Related records in this class

Grouped under Other compounds for navigation only. Shared class membership does not make findings, formulations or evidence interchangeable between records.