21 CFR § 862.1665 - Sodium test system.

---
identifier: "/us/cfr/t21/s862.1665"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "21 CFR § 862.1665 - Sodium test system."
title_number: 21
title_name: "Food and Drugs"
section_number: "862.1665"
section_name: "Sodium test system."
chapter_name: "FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES"
subchapter_number: "H"
subchapter_name: "MEDICAL DEVICES"
part_number: "862"
part_name: "CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "21 U.S.C. 351, 360, 360c, 360e, 360j, 360 371."
regulatory_source: "52 FR 16122, May 1, 1987, unless otherwise noted."
cfr_part: "862"
---


# 862.1665 Sodium test system.

(a) *Identification.* A sodium test system is a device intended to measure sodium in serum, plasma, and urine. Measurements obtained by this device are used in the diagnosis and treatment of aldosteronism (excessive secretion of the hormone aldosterone), diabetes insipidus (chronic excretion of large amounts of dilute urine, accompanied by extreme thirst), adrenal hypertension, Addison's disease (caused by destruction of the adrenal glands), dehydration, inappropriate antidiuretic hormone secretion, or other diseases involving electrolyte imbalance.

(b) *Classification.* Class II.