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 25649-5: Follitropin 6th specimen post Unsp challenge 2nd IRP Qn

Name: LOINC Code 25649-5: Follitropin 6th specimen post Unsp challenge 2nd IRP Qn
Creator: HealthAssure Clinical Team
Published: 2026-05-21T08:59:13.650Z

25649-5 is a LOINC code used to identify Follitropin 6th specimen post Unsp challenge 2nd IRP Qn 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 Follitropin^6th specimen post 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 Follitropin^6th specimen post 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
Method: 2nd IRP

What it does not mean

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

Key facts

Follitropin [Units/volume] in Serum or Plasma by 2nd IRP --6th specimen post XXX challenge
Follitropin^6th specimen post XXX challenge
2nd International Reference Preparation; After; Arbitrary concentration; CHEMISTRY.CHALLENGE TESTING; Follicle stimulating hormone; FSH; IRP2; p chal; Pl; Plasma; Plsm; Point in time; PST; QNT; Quan; Quant; Quantitative; Random; Second; SerP; SerPl; SerPlas; Serum; Serum or plasma; sp6; sp6 p chal; Spec; SR

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

Follitropin 6th specimen post Unsp challenge 2nd IRP QnFollitropin [Units/volume] in Serum or Plasma by 2nd IRP --6th specimen post XXX challengeFSH sp6 p chal SerPl IRP2-aCncFollitropin^6th specimen post XXX challengeCHALFollitropin (FSH; Follicle Stimulating Hormone) 6th specimen after challenge, BloodACnc

Frequently asked questions

Code details

Code25649-5

SystemLOINC

Display nameFollitropin 6th specimen post Unsp challenge 2nd IRP Qn

DescriptionFollitropin^6th specimen post XXX challenge

Short nameFSH sp6 p chal SerPl IRP2-aCnc

ComponentFollitropin^6th specimen post XXX challenge

PropertyACnc

TimingPt

System (specimen)Ser/Plas

ScaleQn

Method2nd IRP

ClassCHAL

Example unitsIU/L;mIU/mL

StatusACTIVE

Order/ObservationObservation

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released2.00

Last changed2.38

Consumer names

Follitropin (FSH; Follicle Stimulating Hormone) 6th specimen after challenge, Blood

Part names

Follitropin^6th specimen post XXX challengeACncPtSer/PlasQn2nd IRPArbitrary 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.