LOINC

LOINC Code 64186-0: At what age did hay fever start [PhenX]

64186-0 is a LOINC code used to identify At what age did hay fever start [PhenX] 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 At what age did hay fever start. It is commonly used with the system or sample type ^Patient.

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 At what age did hay fever start. It is commonly used with the system or sample type ^Patient.

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: TRIAL
  • Method: PhenX

What it does not mean

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

Key facts

  • At what age did hay fever start [PhenX]
  • At what age did hay fever start
  • Hay fever start age; Point in time; QNT; Quan; Quant; Quantitative; Random; Started

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

At what age did hay fever start [PhenX]Hay fever start age PhenXAt what age did hay fever startPHENXTimePt^Patient

Frequently asked questions

Code details

Code64186-0
SystemLOINC
Display nameAt what age did hay fever start [PhenX]
DescriptionAt what age did hay fever start
Short nameHay fever start age PhenX
ComponentAt what age did hay fever start
PropertyTime
TimingPt
System (specimen)^Patient
ScaleQn
MethodPhenX
ClassPHENX
Example unitsyears
StatusTRIAL

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.36
Last changed2.65

Part names

At what age did hay fever startTimePt^PatientQnPhenXTime (e.g. seconds)Point 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.

LOINC Code 64186-0 | HealthAssure