LOINCOrder

LOINC Code 111399-2: Urea nitrogen (U) [Measurement]

111399-2 is a LOINC code used to identify Urea nitrogen (U) [Measurement] 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 Urea nitrogen. It is commonly used with the system or sample type Urine.

Reviewed by HealthAssure Clinical TeamUpdated 21 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 Urea 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: TRIAL
  • Order vs observation: Order

What it does not mean

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

Key facts

Urea nitrogen [Measurement] in Urine
Urea nitrogen
This term is intended to collate similar measurements for the LOINC SNOMED CT Collaboration in an ontological view. Additionally, it can be used to communicate a laboratory order, either alone or in combination with specimen or other information in the order. It may NOT be used to report back the measured patient value. [https//lo.inc/ce2mb6]
Blood urea nitrogen; Lab orders; Msmt; N; N2; Nit; UA; UN; UR; Urn; UUN

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

Urea nitrogen (U) [Measurement]Urea nitrogen [Measurement] in UrineUUN Msmt UrUrea nitrogenLABORDERS.ONTOLOGYUrea Nitrogen (BUN), Urine{Measurement}

Frequently asked questions

Code details

Code111399-2
SystemLOINC
Display nameUrea nitrogen (U) [Measurement]
DescriptionUrea nitrogen
Short nameUUN Msmt Ur
ComponentUrea nitrogen
Property{Measurement}
Timing-
System (specimen)Urine
Scale-
ClassLABORDERS.ONTOLOGY
StatusTRIAL
Order/ObservationOrder

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.81
Last changed2.81

Consumer names

Urea Nitrogen (BUN), Urine

Part names

Urea nitrogen{Measurement}-UrineMeasurement

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 111399-2 | HealthAssure