What does this LOINC code represent?

This LOINC code identifies a lab observation, measurement, question, or clinical concept in a standardized format.

Is this enough to understand my test result?

No. The code identifies the test or observation, but the interpretation depends on the actual result, reference range, and clinical context.

LOINCActiveObservation

LOINC Code 25584-4: Calcium 5 Hr post 500 mg calcium PO (U) [Moles/Vol]

Name: LOINC Code 25584-4: Calcium 5 Hr post 500 mg calcium PO (U) [Moles/Vol]
Creator: HealthAssure Clinical Team
Published: 2026-05-21T08:59:13.649Z

25584-4 is a LOINC code used to identify Calcium 5 Hr post 500 mg calcium PO (U) [Moles/Vol] 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 Calcium^5H post 500 mg calcium PO. 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 Calcium^5H post 500 mg calcium PO. 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: Observation

What it does not mean

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

Key facts

Calcium [Moles/volume] in Urine --5 hours post 500 mg calcium PO
Calcium^5H post 500 mg calcium PO
5h p 500 mg Ca PO; After; Ca; Cal; CHEMISTRY.CHALLENGE TESTING; Level; Point in time; PST; QNT; Quan; Quant; Quantitative; Random; Substance concentration; 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

Calcium 5 Hr post 500 mg calcium PO (U) [Moles/Vol]Calcium [Moles/volume] in Urine --5 hours post 500 mg calcium POCalcium 5h p 500 mg Ca PO Ur-sCncCalcium^5H post 500 mg calcium POCHALCalcium 5 hr after 500 mg Calcium by mouth, UrineSCnc

Frequently asked questions

Code details

Code25584-4

SystemLOINC

Display nameCalcium 5 Hr post 500 mg calcium PO (U) [Moles/Vol]

DescriptionCalcium^5H post 500 mg calcium PO

Short nameCalcium 5h p 500 mg Ca PO Ur-sCnc

ComponentCalcium^5H post 500 mg calcium PO

PropertySCnc

TimingPt

System (specimen)Urine

ScaleQn

ClassCHAL

Example unitsmmol/L

StatusACTIVE

Order/ObservationObservation

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released2.00

Last changed2.70

Consumer names

Calcium 5 hr after 500 mg Calcium by mouth, Urine

Part names

Calcium^5H post 500 mg calcium POSCncPtUrineQnSubstance ConcentrationPoint in time (spot)

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.