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.

LOINC

LOINC Code 65391-5: When did you last take prescription medication for headache on a daily basis to help prevent a severe headache from happening in the first place [PhenX]

Name: LOINC Code 65391-5: When did you last take prescription medication for headache on a daily basis to help prevent a severe headache from happening in the first place [PhenX]
Creator: HealthAssure Clinical Team
Published: 2026-05-21T08:59:44.551Z

65391-5 is a LOINC code used to identify When did you last take prescription medication for headache on a daily basis to help prevent a severe headache from happening in the first place [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 When did you last take prescription medication for headache on a daily basis to help prevent a severe headache from happening in the first place. 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 When did you last take prescription medication for headache on a daily basis to help prevent a severe headache from happening in the first place. 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

When did you last take prescription medication for headache on a daily basis to help prevent a severe headache from happening in the first place [PhenX]
When did you last take prescription medication for headache on a daily basis to help prevent a severe headache from happening in the first place
Finding; Findings; Last took daily med; Ordinal; Past; Point in time; QL; Qual; Qualitative; Random; Rx; Screen

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

When did you last take prescription medication for headache on a daily basis to help prevent a severe headache from happening in the first place [PhenX]Last took daily med PhenXWhen did you last take prescription medication for headache on a daily basis to help prevent a severe headache from happening in the first placePHENXFindPt^Patient

Frequently asked questions

Code details

Code65391-5

SystemLOINC

Display nameWhen did you last take prescription medication for headache on a daily basis to help prevent a severe headache from happening in the first place [PhenX]

DescriptionWhen did you last take prescription medication for headache on a daily basis to help prevent a severe headache from happening in the first place

Short nameLast took daily med PhenX

ComponentWhen did you last take prescription medication for headache on a daily basis to help prevent a severe headache from happening in the first place

PropertyFind

TimingPt

System (specimen)^Patient

ScaleOrd

MethodPhenX

ClassPHENX

StatusTRIAL

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released2.36

Last changed2.65

Part names

When did you last take prescription medication for headache on a daily basis to help prevent a severe headache from happening in the first placeFindPt^PatientOrdPhenXFindingPoint 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.