LOINCActiveObservation

LOINC Code 57649-6: C peptide 1 Hr pre Unsp challenge [Moles/Vol]

57649-6 is a LOINC code used to identify C peptide 1 Hr pre Unsp challenge [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 C peptide^1H pre XXX challenge. It is commonly used with the system or sample type Ser/Plas.

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 C peptide^1H pre XXX challenge. It is commonly used with the system or sample type Ser/Plas.

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

  • C peptide [Moles/volume] in Serum or Plasma --1 hour pre XXX challenge
  • C peptide^1H pre XXX challenge
  • Part of hyperinsulinemic euglycemic clamp test. C peptide is measured during the insulin challenge before glucose injection.
  • 1 hour; 1.0Hr; 1h pre chal; 60 min; 60 minutes; 60M; 60min; Before; CHEMISTRY.CHALLENGE TESTING; Connecting peptide of insulin; Level; Pept; Pl; Plasma; Plsm; Point in time; pre chal; Pro-insulin c peptide; QNT; Quan; Quant; Quantitative; Random; SerP; SerPl; SerPlas; Serum; Serum or plasma; SR; Substance concentration

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

C peptide 1 Hr pre Unsp challenge [Moles/Vol]C peptide [Moles/volume] in Serum or Plasma --1 hour pre XXX challengeC peptide 1h pre chal SerPl-sCncC peptide^1H pre XXX challengeCHALC peptide 1 hr before challenge, BloodSCnc

Frequently asked questions

Code details

Code57649-6
SystemLOINC
Display nameC peptide 1 Hr pre Unsp challenge [Moles/Vol]
DescriptionC peptide^1H pre XXX challenge
Short nameC peptide 1h pre chal SerPl-sCnc
ComponentC peptide^1H pre XXX challenge
PropertySCnc
TimingPt
System (specimen)Ser/Plas
ScaleQn
ClassCHAL
Example unitsnmol/L
StatusACTIVE
Order/ObservationObservation

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.36
Last changed2.70

Consumer names

C peptide 1 hr before challenge, Blood

Part names

C peptide^1H pre XXX challengeSCncPtSer/PlasQnSubstance ConcentrationPoint in time (spot)Serum or Plasma

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 57649-6 | HealthAssure