21 CFR 862.1695
§ 862.1695 Free thyroxine test system.
United States · 21 CFR — Food and Drugs · Status: effective
Cite this
- Citation
- 21 CFR 862.1695, § 862.1695 Free thyroxine test system, United States, version 1 as recorded 2026-07-09, yourstate.us, https://yourstate.us/provision/89189
- Permanent ID
ys:prov:89189@1- SHA-256
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Full text
(a) Identification. A free thyroxine test system is a device intended to measure free (not protein bound) thyroxine (thyroid hormone) in serum or plasma. Levels of free thyroxine in plasma are thought to reflect the amount of thyroxine hormone available to the cells and may therefore determine the clinical metabolic status of thyroxine. Measurements obtained by this device are used in the diagnosis and treatment of thyroid diseases.
(b) Classification. Class II.
Legislative history
This is a federal regulation, adopted through agency rulemaking under the Administrative Procedure Act — not enacted by a recorded vote of Congress.