Urea nitrogen

ChemistryAlso known as: BUN Bld-mCncAlso known as: BUN Bld-sCncAlso known as: BUN BldA-mCncmg/dL

Measures urea nitrogen excretion in serum or plasma to assess protein metabolism.

Normal Range
6 – 20 g/(24.h)
g/(24.h)
Abnormal Levels
Consult your provider
Specimen Type
Blood

Why This Biomarker Matters

Urine urea nitrogen reflects protein metabolism and kidney function. Abnormal levels indicate kidney disease, malnutrition, or metabolic disorders requiring further evaluation.

Understanding Your Results

Normal Range

6 – 20 g/(24.h)

Optimal Ranges

Clinician-defined 4-point reference thresholds (mg/dL)

Default Range

low

high

optimal

borderlineLow

borderlineHigh

Overview

Urea nitrogen in urine reflects protein metabolism and kidney function. This test, typically performed on 12-hour or 24-hour urine collections, measures how much nitrogen from protein breakdown is excreted daily. Abnormal levels can indicate dietary protein intake changes, kidney disease, liver dysfunction, or metabolic disorders. The test helps assess protein metabolism, evaluate kidney function, and monitor nutritional status in patients with various metabolic or renal conditions.

Related Health Conditions

Conditions where Urea nitrogen is commonly tested

Chronic kidney disease

Hyperkalemia

Hyponatremia

Proteinuria

Related Health Goals

Improve Kidney Health

Optimize Electrolyte Balance

Treatments & Interventions

Therapies monitored using Urea nitrogen

Sodium acetate

Sodium chloride

Conivaptan

Conivaptan hydrochloride

Tolvaptan

Sodium acetate anhydrous

Clinical Trials

61
Total Trials
12
Recruiting
10
With Results

Recent Trials

Family Investigation of Nephropathy and Diabetes (F.I.N.D.)

NCT00342927Recruiting100,000 enrolled

Study of Ravulizumab in Immunoglobulin A Nephropathy (IgAN)

NCT06291376Phase 3Recruiting510 enrolled

Empagliflozin Treatment in Kidney Transplant Recipients

NCT06013865Phase 4Recruiting264 enrolled

Nefecon and Ambrisentan in IgA Nephropathy

NCT07030894Phase 4Recruiting129 enrolled

A Study to Learn More About How Safe the Study Treatment Finerenone is in Long-term Use When Taken With an ACE Inhibitor or Angiotensin Receptor Blocker Over 18 Months of Use in Children and Young Adults From 1 to 18 Years of Age With Chronic Kidney Disease and Proteinuria

NCT05457283Phase 3Recruiting100 enrolled
View all 61 trials on ClinicalTrials.gov

Research & Evidence

2 publications

Technical Information (LOINC Codes)

Standardized laboratory codes for this biomarker

3094-0Primary
Urea nitrogen [Mass/volume] in Serum or Plasma
mg/dL
3096-5
Urea nitrogen [Mass/time] in 24 hour Urine
g/(24.h)
6299-2
Urea nitrogen [Mass/volume] in Blood
mg/dL
3093-2
Urea nitrogen [Mass/volume] in Body fluid
mg/dL
3095-7
Urea nitrogen [Mass/volume] in Urine
mg/dL
24465-7
Urea nitrogen [Mass/time] in 12 hour Urine
g/(12.h)
12963-5
Urea nitrogen [Mass/volume] in Peripheral blood
mg/dL
14939-3
Urea nitrogen [Moles/time] in 24 hour Urine
mmol/(24.h)
12961-9
Urea nitrogen [Mass/volume] in Arterial blood
mg/dL
12265-5
Urea nitrogen [Mass/volume] in Peritoneal fluid
mg/dL
59570-2
Urea nitrogen [Moles/volume] in Blood
mmol/L
5918-8
Urea nitrogen [Mass/volume] in Dialysis fluid
mg/dL
12962-7
Urea nitrogen [Mass/volume] in Venous blood
mg/dL
12967-6
Urea nitrogen [Mass/volume] in 24 hour Urine
mg/dL
14937-7
Urea nitrogen [Moles/volume] in Serum or Plasma
mmol/L
14396-6
Urea nitrogen [Mass/volume] in Synovial fluid
mg/dL
14936-9
Urea nitrogen [Moles/volume] in Peritoneal dialysis fluid
mmol/L
14393-3
Urea nitrogen [Mass/volume] in Amniotic fluid
mg/dL
14000-4
Urea nitrogen [Mass/volume] in Cerebral spinal fluid
mg/dL
33355-9
Urea nitrogen [Moles/volume] in 24 hour Urine
mmol/L
14394-1
Urea nitrogen [Mass/volume] in Pleural fluid
mg/dL
14938-5
Urea nitrogen [Moles/volume] in Urine
mmol/L
14397-4
Urea nitrogen [Mass/volume] in Gastric fluid
mg/dL
17757-6
Urea nitrogen [Mass/volume] in Peritoneal dialysis fluid
mg/dL
17758-4
Urea nitrogen [Mass/volume] in Vitreous fluid
mg/dL

Available Lab Tests

Order tests that measure this biomarker

Adrenal Complete

$340.56

Advanced Cardiovascular Health Basic

$132.55

Advanced Cardiovascular Health Comprehensive

$526.57

Advanced Liver Health Basic

$293.92

Advanced Liver Health Comprehensive

$1044.34

Cancer Tumor Markers Men Basic

$71.57

Comprehensive Metabolic Panel (CMP)

$15.79
Results in Same day to 1 business day

Find Specialists

Doctors who commonly order this test

Internal Medicine
Endocrinology, Diabetes & Metabolism
Nephrology
Urea nitrogen: Normal Range, Testing & Clinical Significance | Healos | Healos