21 CFR § 862.1555 - Phenylalanine test system.

---
identifier: "/us/cfr/t21/s862.1555"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "21 CFR § 862.1555 - Phenylalanine test system."
title_number: 21
title_name: "Food and Drugs"
section_number: "862.1555"
section_name: "Phenylalanine 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"
---


# 862.1555 Phenylalanine test system.

(a) *Identification.* A phenylalanine test system is a device intended to measure free phenylalanine (an amino acid) in serum, plasma, and urine. Measurements of phenylalanine are used in the diagnosis and treatment of congenital phenylketonuria which, if untreated, may cause mental retardation.

(b) *Classification.* Class II.