{"data":{"id":"us/21-cfr-862.1555","jurisdiction":"us","citation":"21 CFR 862.1555","heading":"Phenylalanine test system.","body":"(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.\n(b) Classification. Class II.","path":["Title 21—Food and Drugs","CHAPTER I—FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES","SUBCHAPTER H—MEDICAL DEVICES","PART 862—CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES","Subpart B—Clinical Chemistry Test Systems"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-21.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:24:47Z","sha256":"a1cdf593f60e9a4ba80959b2ec9afb28a6f819ab25aec270161e77e62b8a9983","source_id":"us-cfr","stale":true,"prev":"us/21-cfr-862.1550","next":"us/21-cfr-862.1560"},"notice":"GroundRules: Original legal text. Not legal advice."}