LOINCActiveBoth

LOINC Code 40391-5: Para aminobenzoate free [Mass/Vol]

40391-5 is a LOINC code used to identify Para aminobenzoate free [Mass/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 Para aminobenzoate.free. 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 Para aminobenzoate.free. 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: Both

What it does not mean

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

Key facts

  • Para aminobenzoate free [Mass/volume] in Serum or Plasma
  • Para aminobenzoate.free
  • Aminobenzoic acid; c701; DRUG/TOXICOLOGY; Drugs; FR; Level; Mass concentration; Non-protein bound; p Aminobenzoate; PAB; PABA; pABA Free; Pabanol; Pl; Plasma; Plsm; Point in time; QNT; Quan; Quant; Quantitative; Random; SerP; SerPl; SerPlas; Serum; Serum or plasma; 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

Para aminobenzoate free [Mass/Vol]Para aminobenzoate free [Mass/volume] in Serum or PlasmapABA Free SerPl-mCncPara aminobenzoate.freeDRUG/TOXFree para aminobenzoate, BloodMCnc

Frequently asked questions

Code details

Code40391-5
SystemLOINC
Display namePara aminobenzoate free [Mass/Vol]
DescriptionPara aminobenzoate.free
Short namepABA Free SerPl-mCnc
ComponentPara aminobenzoate.free
PropertyMCnc
TimingPt
System (specimen)Ser/Plas
ScaleQn
ClassDRUG/TOX
Example unitsmg/L
StatusACTIVE
Order/ObservationBoth

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.15
Last changed2.70

Consumer names

Free para aminobenzoate, Blood

Part names

Para aminobenzoate.freeMCncPtSer/PlasQnPara aminobenzoate freeMass 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 40391-5 | HealthAssure