LOINCActiveBoth

LOINC Code 1843-2: Ammonia nitrogen (24H U) [Mass/Time]

1843-2 is a LOINC code used to identify Ammonia nitrogen (24H U) [Mass/Time] in laboratory and clinical observation data. You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges. LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Ammonia nitrogen. It is commonly used with the system or sample type Urine.

Reviewed by HealthAssure Clinical TeamUpdated 25 May 2026

What is this code?

LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Ammonia nitrogen. It is commonly used with the system or sample type Urine.

When is it used?

  • Used in lab systems, EHRs, and clinical data exchange.
  • May identify a test, observation, survey item, or clinical document request rather than a diagnosis.
  • Status: ACTIVE
  • Order vs observation: Both

What it does not mean

  • The code identifies the observation or test, not the actual result.

Key facts

  • Ammonia nitrogen [Mass/time] in 24 hour Urine
  • Ammonia nitrogen
  • 1 day; 24 hours; 24HR; Amm; Ammon; Ammonium nitrogen; Amon; Chemistry; Kidney; Mass Rate; mRate; N; N2; Nephrology; NH3; Nit; QNT; Quan; Quant; Quantitative; Renal; UA; UR; Urn

Where you may see this code

You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges.

Common synonyms

Ammonia nitrogen (24H U) [Mass/Time]Ammonia nitrogen [Mass/time] in 24 hour UrineAmmonia nitrogen 24h Ur-mRateAmmonia nitrogenCHEMAmmonia nitrogen, UrineMRat

Frequently asked questions

Code details

Code1843-2
SystemLOINC
Display nameAmmonia nitrogen (24H U) [Mass/Time]
DescriptionAmmonia nitrogen
Short nameAmmonia nitrogen 24h Ur-mRate
ComponentAmmonia nitrogen
PropertyMRat
Timing24H
System (specimen)Urine
ScaleQn
ClassCHEM
Example unitsug/24 H
StatusACTIVE
Order/ObservationBoth

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released1.0
Last changed2.73

Consumer names

Ammonia nitrogen, Urine

Part names

Ammonia nitrogenMRat24HUrineQnMass Rate24 hours

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from LOINC. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.

LOINC Code 1843-2 | HealthAssure